http://www.keyspan.com/products/usb/server/ is the one I was thinking of. It's not wifi as I remembered, but that's better in my book. I can't imagine the latency would make it workable for mice and keyboards, but I've never used one. Definitly a neat hack for laptop people.

I'll seccond your addiction to the Logitech Trackman Marble. I used to be addicted before I switched to using a laptop. I still miss mine and check for a bluetooth one on logitech's site every few months.

Matthew