I just got my Picopad in the mail and slipped it into my wallet. Everything seems as advertised so far, but I have yet to try it out in a live environment.
I've loved my Signature knife for a long time, but I've had a problem with using it while traveling. I don't like to take it off my keyring and check the knife, so I'm stuck leaving it at home, and it's when I travel that I seem to need it most. 90% of the time I pull the knife out is to use the pen that it has. The picopad solves this problem, and gives me something to write on as well. When not traveling, I'll almost definitely keep my knife with me, but now it's not so critical.