Probably what you should be doing right now...
Instead you come here to procrastinate.
Hmm I need to revise, hell lets look up revision at urbandictionary to waste some time.
Used as shorthand in online conversations to substitute 'especially'.
Person 1: Wow that concert was ace!
Person 2: Yeh the drummer was esp good.
When your or someone else's birthday was yesterday.
Brian: I had a great birthday yesterday.
Fred: Happy Yesterbirthday Brian!
Person 1: Damn the movie I just downloaded isn't working!
Person 2: Just redl mate.
This is said when you forgot to tell a person happy birthday, and only remember the day after.
Bill: I had a great birthday yesterday...
Fred: Shit! Happy Yesterbirthday!
Massively Multiplayer Online Crack House.
This pretty much describes any MMORPG in existance. The unique qualities of these games are comparable to that of a crack house. Users go in, get completely addicted, and find it difficult to leave.
Person 1: So what MMORPG do you play?
Person 2: MMORPG? I play WoW, it's pretty much an MMOCH.