ELECTRONICS
Here some useful links to search for datasheets:
www.datasheetcatalog.com
www.alldatasheet.com
The IC TC74 is a small temperature sensor that communicate over the I²C bus
Here a link to an USB to I²C bus tool, very cheap and great tool to test I²C communication.
The I²C interface program is very simple, yet very powerful and cheap compared to professional development tools.
USB to I²C
Links:
Small example of sending infrared commands to TV and amplifier, written in C.
Projects:
Kicken timer with 4 timers, written in PicBasic for dsPIC.
The MCP9808 readout for raspberry pi has moved to the android / B4J  section.