Another term for hackspeak. The normal letters are replaced with symbols and numbers. Used by k3wl d00dz, people making fun of them, and people who want to piss off newbies who don't understand it. Here is a heavily l33t speaked example:

p|-|34r (\/)3 1 0\/\/(\) j00 !!! 1 @(\/) |337! = Fear me I own you! I am elite!