I recently acquired 4 Philips wireless keyboards. These are only slightly larger than the Douphin keyboards, and are IR wireless to 16 feet. The keyboard itself requires 2 AAA batteries, and the reciever simply plugs into a PS2 keyboard port. There are no drivers. The only thing you have to do is relabel some of the keys (if you want to) to make it look more like a standard PC keyboard.

I am selling them for $30 US, and making no profit off of this. Shipping extra....

Pictures below: