My school started requiring ID checks upon entry to campus, and I got tired of digging mine out of my actual wallet, so I found a stashed roll or two of duct tape in my room and voila, ID wallet...which also conviniently serves to hold ATM cards and cash
... I should have covered it with packing tape, because it's starting to get a little gummy at the edges of the tape strips.
I also made the checkbook cover because my checkbooks kept getting bent up in my bag...I covered most of it with a layer of packing tape, though, to prevent the gummy syndrome...and i plan to add velcro to the little flap, to keep it closed.
Here's a kind of tutorial on how to make the checkbook cover...if you want to do duct tape stencils, you just make a sheet of sticky contrasting color duct tape (don't turn over when you layer), and cut out a stencil like you would normally, then stick it on...and cover with clear packing tape if you know what's good for you!