This project is more hardware related - it's an infrared remote control library for the TI-83 series calculators. It supports the SIRCS (Sony) protocol, with command words of 12, 15 and 20 bits.
Video of the library in action (960KB WMV).
The hardware is very simple if you just want to transmit, and a single-package infrared receiver/amplifier/demodulator makes the receiving circuit not that much more complex.
The library also comes with a program that can be used to turn an 83+ into a programmable remote control. It supports multiple device profiles, and editing is easy - press the key (on the calculator) you wish to customise, point your remote at the receiver and press the button you want change to and the details are automatically saved.
SonyIR download page and documentation.