I just tried the Logitech PS3 wireless bluetooth keyboard and it appears to work perfectly with the TP, with the touch pad working as the mouse pointer with better responsiveness than a typical laptop touch pad. The thing now is to find if the keyboard PS3-specific buttons can also be mapped. The Logitech keyboard is really light and they complement each other well.

Logitech Cordless MediaBoard Pro for PS3

The bluetooth pairing with the TP is really slick and now it will be some exploration to find out how versatile it is. It's also supposed to provide a bluetooth wireless connection between the TP and a PC or laptop with bluetooth.