We've purchased two refurbished RM tablets for £103 a piece as an experiment. Obviously when you get Tablet PCs for that kind of price they don't come ready to go, so after a bit of fiddling they now have Windows XP Tablet edition 2005 installed. They also didn't come with styli (the touchscreen is RF based not touch sensitive) so I've ordered some replacements from RM, in the mean time we're using some old Wacom tablet styli which work reasonably well.
They'll be used by various members of staff over the coming weeks and months so that we can decide whether tablets are a viable device for our use.