a. Anything that is messed up really bad.
b. Used to curse at something that didn't go your way.
c. A thing that annoys or pisses you off.
d. (Used occassionally) Someone who has a really weird or unusual personality and/or does stuff that just aren't "normal."
Yo, everybody got a D or F on the exam! That shit's fucked up, man, why won't the teacher cuve it?
Yeah, I know, I used the system to do a check-over on my projet but it completely destroyed it instead! That shit's completely fucked up!
The chess computer keeps moving my own pieces! That shit's completely fucked up, dude. You can have it.