=|
1. It's a "blank face." Usually it means you don't have anything to say or are confuzed about something previously said. It's probably one of the worst things to use if you have any intention of carrying on a real conversation (a.k.a. more than a few words.) It is also commonly used in cynisism of a previous statement.

2. The face known to Jhonen Vasquez fans as the "squee face" because a character from one of his comics wears the symbol on his shirt.
1.
Person #1: lolololololololololololol
Person#2: ... no =|

2. =| (but on a shirt)