diff --git a/Pipfile b/Pipfile
index 6b7566a..f536374 100644
--- a/Pipfile
+++ b/Pipfile
@@ -6,6 +6,9 @@ name = "pypi"
 [packages]
 matrix-nio = "*"
 geopy = "*"
+google-api-python-client = "*"
+google-auth-httplib2 = "*"
+google-auth-oauthlib = "*"
 
 [dev-packages]
 pylint = "*"
diff --git a/README.md b/README.md
index c52632e..0625140 100644
--- a/README.md
+++ b/README.md
@@ -1,15 +1,59 @@
-# Hemppa - generic Matrix bot
+# Hemppa - generic modular Matrix bot
+
+This bot is meant to be super easy platform to code Matrix bot functionality
+with Python. It uses matrix-nio library https://github.com/poljar/matrix-nio/ .
+
+Type !help in room with this bot running to list active modules.
 
 ## Module list
 
-Write !modulename in Matrix room where the bot is to use modules.
+### Help
+
+Prints help on existing modules.
 
 ### Echo
 
-Simple example module that just echoes what user said. Can be used as an
-example for writing own modules.
+Simple example module that just echoes what user said.
 
-## First
+### Metar
+
+Aviation weather metar service access.
+
+### TAF 
+
+Aviation weather TAF service access.
+
+### Uptime
+
+Prints bot uptime.
+
+### Google Calendar (WIP)
+
+Displays changes and daily report of a google calendar to a room. This is a bit pain to set up, sorry.
+
+To set up, you'll need to generate credentials.json file - see https://console.developers.google.com/apis/credentials
+
+When credentials.json is present, you must authenticate the bot to access calendar. There will be a link in console like this:
+
+``` text
+Please visit this URL to authorize this application: https://accounts.google.com/o/oauth2/auth?response_type=code&client_id=907....
+```
+
+Open the link and authenticate as needed. A new file token.pickle will be created in the directory and bot will read it in future. 
+
+Now the bot should be usable.
+
+Use !googlecal add [calendar id] to add new calendar to a room. The bot lists availble calendar ID's on startup and you can find them
+in google calendar.
+
+Commands:
+
+* !googlecal - Show next 10 events in calendar
+* !googlecal today - Show today's events
+* !googlecal add [calendar id] - Add new calendar to room
+* !googlecal calendars - List calendars in this room
+
+## Bot setup
 
 * Create a Matrix user
 * Get user's access token - In Riot Web see Settings / Help & about
@@ -51,4 +95,17 @@ join invites automatically.
 
 You can set MATRIX_PASSWORD if you want to get access token. Normally you can use Riot to get it.
 
-## Testing
+## Module API
+
+Just write a python file with desired command name and place it in modules. See current modules for
+examples. No need to register it anywhere else.
+
+Functions:
+
+* matrix_start - Called once on startup
+* async matrix_message - Called when a message is sent to room starting with !module_name
+* matrix_stop - Called once before exit
+* async matrix_poll - Called every 10 seconds
+* help - Return one-liner help text
+
+You only need to implement the ones you need. See existing bots for examples
diff --git a/bot.py b/bot.py
index a1afb74..6a20a33 100755
--- a/bot.py
+++ b/bot.py
@@ -15,6 +15,8 @@ class Bot:
     client = None
     join_on_invite = False
     modules = dict()
+    pollcount = 0
+    poll_task = None
 
     async def send_text(self, room, body):
         msg = {
@@ -23,6 +25,14 @@ class Bot:
         }
         await self.client.room_send(self.get_room_id(room), 'm.room.message', msg)
 
+    async def send_html(self, room, html):
+        msg = {
+            "msgtype": "m.text",
+            "format": "org.matrix.custom.html",
+            "formatted_body": html
+        }
+        await self.client.room_send(self.get_room_id(room), 'm.room.message', msg)
+
     def get_room_id(self, room):
         for roomid in self.client.rooms:
             if self.client.rooms[roomid].named_room_name() == room.named_room_name():
@@ -83,6 +93,17 @@ class Bot:
             if moduleobject:
                 self.modules[modulename] = moduleobject
 
+    async def poll_timer(self):
+        while True:
+            self.pollcount = self.pollcount + 1
+            for modulename, moduleobject in self.modules.items():
+                if "matrix_poll" in dir(moduleobject):
+                    try:
+                        await moduleobject.matrix_poll(bot, self.pollcount)
+                    except:
+                        traceback.print_exc(file=sys.stderr)
+            await asyncio.sleep(10)
+
     def init(self):
         self.client = AsyncClient(os.environ['MATRIX_SERVER'], os.environ['MATRIX_USER'])
         self.client.access_token = os.getenv('MATRIX_ACCESS_TOKEN')
@@ -116,6 +137,7 @@ class Bot:
             print("Logged in with password, access token:", self.client.access_token)
 
         await self.client.sync()
+        self.poll_task = asyncio.get_event_loop().create_task(self.poll_timer())
 
         if self.client.logged_in:
             self.client.add_event_callback(self.message_cb, RoomMessageText)
@@ -134,5 +156,7 @@ bot.init()
 try:
     asyncio.get_event_loop().run_until_complete(bot.run())
 except KeyboardInterrupt:
-    pass
+    if bot.poll_task:
+        bot.poll_task.cancel()
+
 bot.stop()
diff --git a/modules/googlecal.py b/modules/googlecal.py
new file mode 100644
index 0000000..3385430
--- /dev/null
+++ b/modules/googlecal.py
@@ -0,0 +1,173 @@
+from __future__ import print_function
+from datetime import datetime
+import datetime
+import pickle
+import os.path
+import time
+import os
+
+from googleapiclient.discovery import build
+from google_auth_oauthlib.flow import InstalledAppFlow
+from google.auth.transport.requests import Request
+
+
+
+#
+# Google calendar notifications
+#
+# Note: Provide a token.pickle file for the service. 
+# It's created on first run (run from console!) and 
+# can be copied to another computer.
+#
+# ENV variables:
+#
+# Google calendar creds file: (defaults to this)
+# GCAL_CREDENTIALS="credentials.json"
+#
+
+class MatrixModule:
+    def matrix_start(self, bot):
+        self.bot = bot
+        self.SCOPES = ['https://www.googleapis.com/auth/calendar.readonly']
+        self.credentials_file = "credentials.json"
+        if os.getenv("GCAL_CREDENTIALS"):
+            self.credentials_file = os.getenv("GCAL_CREDENTIALS")
+        self.service = None
+        self.report_time = 8
+        self.last_report_date = None
+        self.calendar_rooms = dict() # Contains rooms -> [calid, calid] ..
+
+        creds = None
+
+        if not os.path.exists(self.credentials_file):
+            return # No-op if not set up
+
+        if os.path.exists('token.pickle'):
+            with open('token.pickle', 'rb') as token:
+                creds = pickle.load(token)
+        # If there are no (valid) credentials available, let the user log in.
+        if not creds or not creds.valid:
+            if creds and creds.expired and creds.refresh_token:
+                creds.refresh(Request())
+            else:
+                flow = InstalledAppFlow.from_client_secrets_file(
+                    self.credentials_file, self.SCOPES)
+                creds = flow.run_local_server(port=0)
+            # Save the credentials for the next run
+            with open('token.pickle', 'wb') as token:
+                pickle.dump(creds, token)
+
+        self.service = build('calendar', 'v3', credentials=creds)
+
+        calendar_list = self.service.calendarList().list().execute()['items']
+
+        print(f'Google calendar set up successfully with access to {len(calendar_list)} calendars:\n')
+        for calendar in calendar_list:
+            print(calendar['summary'] + ' - ' + calendar['id'])
+
+
+    async def matrix_message(self, bot, room, event):
+        if not self.service:
+            await bot.send_text(room, 'Google calendar not set up for this bot.')
+            return
+        args = event.body.split()
+        events = []
+        calendars = self.calendar_rooms.get(room) or []
+
+        if len(args) == 2:
+            if args[1] == 'today':
+                for calid in calendars:
+                    print('Listing events in cal', calid)
+                    events = events + self.list_today(calid)
+            if args[1] == 'calendars':
+                await bot.send_text(room, 'Calendars in this room: ' + str(self.calendar_rooms.get(room)))
+        elif len(args) == 3:
+            if args[1] == 'add':
+                calid = args[2]
+                print(f'Adding calendar {calid} to room {room}')
+
+                if self.calendar_rooms.get(room):
+                    self.calendar_rooms[room].append(calid)
+                else:
+                    self.calendar_rooms[room] = [calid]
+
+                print(f'Calendars now for this room {self.calendar_rooms[room]}')
+
+                await bot.send_text(room, 'Added new google calendar to this room')
+        else:
+            for calid in calendars:
+                print('Listing events in cal', calid)
+                events = events + self.list_upcoming(calid)
+
+            if len(events) == 0:
+                await bot.send_text(room, 'No events found.')
+            else:
+                print(f'Found {len(events)} events')
+                await self.send_events(bot, events, room)
+
+    async def send_events(self, bot, events, room):
+        for event in events:
+            start = event['start'].get('dateTime', event['start'].get('date'))
+            await bot.send_text(room, f"{self.parseDate(start)} {event['summary']}")
+            # await bot.send_text(room, f"{self.parseDate(start)} {event['summary']} {event['htmlLink']}")
+            # await bot.send_html(room, self.parseDate(start) + " <a href=\"" + event['htmlLink'] + "\">" + event['summary'] + "</a>")
+
+    def list_upcoming(self, calid):
+        startTime = datetime.datetime.utcnow()
+        now = startTime.isoformat() + 'Z'
+        events_result = self.service.events().list(calendarId=calid, timeMin=now,
+                                            maxResults=10, singleEvents=True,
+                                            orderBy='startTime').execute()
+        events = events_result.get('items', [])
+        return events
+
+    def list_today(self, calid):
+        startTime = datetime.datetime.utcnow()
+        startTime = startTime - datetime.timedelta(hours=startTime.hour, minutes=startTime.minute)
+        endTime = startTime + datetime.timedelta(hours=24)
+        now = startTime.isoformat() + 'Z'
+        end = endTime.isoformat() + 'Z'
+        events_result = self.service.events().list(calendarId=calid, timeMin=now,
+                                                    timeMax=end, maxResults=10, singleEvents=True,
+                                            orderBy='startTime').execute()
+        events = events_result.get('items', [])
+        return events
+
+    async def matrix_poll(self, bot, pollcount):
+        if not self.service:
+            return
+
+        if pollcount % (6 * 5) == 0: # Poll every 5 min
+            pass # Not implemented yet
+
+        needs_send = False
+
+        today = datetime.datetime.now()
+        since_last = 999
+
+        # Bot's been started
+        if self.last_report_date:
+            since_last = (today - self.last_report_date).total_seconds() / 60 / 60
+
+        if since_last > 20 and today.hour >= self.report_time:
+            needs_send = True
+
+        if needs_send:
+            self.last_report_date = today
+
+            for room in self.calendar_rooms:
+                events = []
+                for calid in self.calendar_rooms.get(room):
+                    events = events + self.list_today(calid)
+                await self.send_events(bot, events, room)
+
+    def help(self):
+        return('Google calendar. Lists 10 next events by default. today = list today\'s events.')
+
+    def parseDate(self, start):
+        try: 
+            dt = datetime.datetime.strptime(start, '%Y-%m-%dT%H:%M:%S%z')
+            return dt.strftime("%d.%m %H:%M")
+        except ValueError:
+            dt = datetime.datetime.strptime(start, '%Y-%m-%d')
+            return dt.strftime("%d.%m")
diff --git a/modules/help.py b/modules/help.py
new file mode 100644
index 0000000..4449a95
--- /dev/null
+++ b/modules/help.py
@@ -0,0 +1,16 @@
+class MatrixModule:
+    async def matrix_message(self, bot, room, event):
+        msg = 'This is Hemppa, a generic Matrix bot. Known commands:\n\n'
+
+        for modulename, moduleobject in bot.modules.items():
+            msg = msg + '!' + modulename
+            try:
+                msg = msg + ' - ' + moduleobject.help() + '\n'
+            except AttributeError:
+                pass
+            msg + msg + '\n'
+        msg = msg + "\nAdd your own commands at https://github.com/vranki/hemppa"
+        await bot.send_text(room, msg)
+
+    def help(self):
+        return('Prints help on commands')