[harryzhang]

This is awesome but I'm concerned about how it would be too easy to switch cards (accidentally). In the FAQ they say it's fine if its dropped, handed into a booklet, etc. Sounds fine in theory but what happens when you hand the card to the waiter/bartender and they happen just to grab it where the circle is? Won't that change the card?

Another concern is in bars - your CC# gets a tiny bit wet (drunk ppl, spilled drinks on table, etc.). Does this card stop working if its splashed a little?

My two cents.

This is awesome though.