A4Tech's Battery-Free Mouse uses RFID
by TreeHugger on 11.10.04
The new A4Tech wireless optical mouse may not be a looker, but we give it props for going battery-free. Although you have to use a special RFID (radio frequency identification) mouse pad to make it work, it powers up directly from there, saving you from the unnecessary cost, guilt, and pollution of throw-away batteries. Via Gizmodo ::A4 Tech
... and so does using a corded mouse -- why have cordless if you're tied to the pad? It defeats the purpose. Plus, you can get a corded optical mouse for five dollars.