This is the technique i use for making simple, cheap handcuff shims for use at parties or places where i don't mind losing them. The shims available through SERE Pick are outstanding, and i highly recommend them... but in a pinch this will work well, especially if all you are doing is having some fun with friends.
Always remember:
1. This will only work if a cuff is not double-locked. Hence, if the cuffs are applied quickly and in a cursory manner.
2. Naturally, you don't ever pull this kind of nonsense in a legitimate custodial situation with actual law enforcement. Cops think escaping handcuffs is funny, but not if they are detaining you at the time.
3. Don't cuff yourself when you're totally alone, with no easy way of calling for help or getting unlocked... particularly behind your back! :-)
