The devious but non-harmful tricks played on other internet users or MMO players. Usually preformed by griefers or trolls, but sometimes by just people in good taste. More complex ones may be done by script kiddies.
(In a game of tf2)
Player 1: Why does our entire team consist of sandvich heavies?
Player 2: :3
Player 1: Enough of this catfacery.
(In Chatroulette)
*You see stranger's feed as a copy of yourself*
Stranger: :3
You: -_- *nexted*
When someone uses the 'cat face' emoticon ":3" at a time when it's not reallyappropriate, much to the annoyance of the people receiving the text.
Example 1:
Joe (texting): Hey man, do you think you'll be able to pick me up after the show?
Ricardo (texting back): :3
Dave (to Joe): Looks like you just got catfaced.
Example 2:
Joe: Hey, want to go out for a beer later on?
Ricardo: :3
Joe: Yeah, that doesn't help me.