new feature on Facebook is known as Easter Egg of Facebook Avatar.
Facebook has recently started where users can create their own Facebook profile picture as a Facebook smiley. This also can be used to create Facebook fan pages smiley.
It’s simple just type in [[your id]] or [[username]]
Check the below video tutorial.
Also there’s a new Facebook Like smiley. Type (Y)
Some old Facebook chat tricks.
To write text in bold. Type *your text*
To write underline text. Type _your text_
Note: - This works only in Facebook chat.
Check out the Facebook Cheat Codes too.