Using a Xantech IR emitter for TiVo control of an external receiver

"Using a Xantech IR emitter for TiVo control of an external receiver by Matthew Gast -- Now that TiVo has broken serial port control of my external receiver, I needed to revert to infrared emitters. After trying to make the TiVo-supplied emitters work, I bought a replacement that performs a bit better."

It has other applications as well. Overall, the nice thing about it is that it is so small. So many of these types of things end up having a large interface to stick on the front of your device.