How-To Turn your iPod in to a Universal Infrared Remote Control - Features - features.engadget.com

This is really cool:

"Basically, we recorded the sounds an infrared remote makes on a PC and then put them on an iPod as songs. Adding a special sound-to-IR converter then turns those sounds back to IR and allows you to use your iPod as a remote control. As an added bonus, it works up to 100 feet. It's a slick all-in-one unit and we're never going back to 6 remotes ever again."