The Number Game:
Here's how it works.
You send a friend on your friends list a single number to their in-box.
Once they receive that number they post on their wall what they think about you, or a memory they have about you. But they don't use your name they simply put the number.

Ex:
inbox
new message from FB User
#7

On your wall you write:

#7 I remember that one time when we were at the park and you were trying to impress "Jason" and you jumped off the swing and totally did a face plant. Talk about embarrassing. I love you <3 !!