Already been done
*** Duplicated from another post about controlling relays with your iPod touch. I've been meaning to post this one in the forum for folks to get some inspiration from. It's conspicuous by its absence here! Thanks to 4ofakind for posting about it. - Admin [Bugbyte] ***
Try this link:
I'm surprised it has not been discussed sooner. Try searching "RedEye" from ThinkFlood. RedEye is a hardware and software combo which communicates with iPods over wifi and relays the signals to whatever you want to control.
Hope this helps.