I don't know what the F*** that means but anyway...
I think the words say it all, but basically, when there is something you completely don't understand, but don't care to take the time to understand it.
Umm, I have no idea what kind of situation i could give an example of... How's about: A nerd tells ya some stuff about computers that is too freakin' complicated for any non superbrained human to understand. So you say: Idkwtftmba!
Cigarette: Northern slang for a cigarette, used oft by mashed up mancunian ravers becasue of the resemblance of a hot(electric)stove to the end of a lit cigarette. Originated circa 1991 in the early halcyon days of the rave culture; we speculate during a drug fuelled hallucination by said manc.
'fuck me noel, i am bolloxed, is that a ciggy in your mouth, or the stove from me 'nans kitchen'/
General use: 'Give us a stove you cunt'