The mobile phone does what you think it does.
Anyremote gives you a way to control a PC with a mobile phone or PDA via Bluetooth, IR or a plain cable. Read about it, it’s cool. In setting up a MythTV box (more on it later), I was a bit stuck for how to control the thing – eventually I’ll dig an IR receiver out of somewhere, and train it to use a DVD remote control or something, but until then I had a USB keyboard with a very short cable. Or until I actually made practical use of my phone’s Bluetooth capabilities and made a remote control out of that instead.
Besides, controlling your computer with your mobile phone is really really cool.