This is a response to dogsrcool2me's 'RFID Secure Wallet.' It's the same concept, except it's made out of two soda cans and some packaging tape. And it's very sloppy. In fact, I'm quite ashamed of my sloppiness.
I would suggest using duct tape, but I didn't have any around. So, here we go.
2 soda cans
packing tape/duct tape
felt tip pen
Step 1: Step one
Get a hold of two cans of soda. Either dump them out or give one to your very close, anonymous anarchist friend.