An emoticon used to imply that you aren't impressed.
Person 1: I have the coolest hat in the world!
Person 2: ;l
A very morbid and attention-seeking smiley. Mostly said by people who fake being angry so they can get attention from their peers.
Cameron: omg wtf daniel just blocked me on msn ;l
Lauren: nawwwwwww its ok don't worry about daniel, he's just being mean.. just talk to sienna instead