When I concluded my Thinkpad Tablet 2 was a little bit too small to work as a primary machine (switched to a Helix 2 for that), I re-paired the bluetooth keyboard w/optical trackpoint with my tablet. The keyboard fits inside my jacket.

I can't express quite how wonderful it is on the occasions I don't have a bag with me to still be able to have a proper keyboard+mouse setup when something goes sideways.