Here is my little project with ESP8266 using Arduino IDE. (Many thanks to Ivan (@igrr) for his incredible work on the SSL client).
We can now read/write to Google spreadsheet directly. You can fetch calendar events, and also "chat" with your ESP8266 This library implements the url forwarding used by Google so you can seamlessly get the required data.
No need to use 3rd party forwarding services like pushingbox or IFFTT.
You can directly log sensor data to Google spreadsheets and read back. It can be used for any other kind of service too, which implements http request-forwarding.
Please let me know of your comments and suggestions.