[Emanuele] is using Google Docs to log his temperature sensor data automatically (translated). We can see a few benefits gained by using this system. One is that you don’t have to visit the site of the logging hardware to harvest the data, another is that Google will automatically graph the data for you. Of course this means you need some way to connect your logger to the Internet, but we’ve seen buckets of different techniques for doing so. In this case, [Emanuele] is using PIC hardware that has a NIC on the board. But the technique could be used from a computer just as easily as from a microcontroller.
The meat and potatoes of the hack is sniffing out the HTTP header and syntax for writing to cells on a Google Docs (soon to be Google Drive) spreadsheet. After making a new spreadsheet and copying the URL and key from the address bar, he loads up the page using a header-viewer web service. With all the pertinent info in hand he crafts about a dozen lines of code to assemble the HTTP packet, and rolls the timestamp and temperature reading into it dynamically. See the system in action after the break.