Pozdro & kasa? - examples of Polish word abbreviations

How long has the tendency to abbreviate common terms been around 5, 10, 15 years or more? I refer to such things as pozdro, nara, spoko, siema, etc. Does anyone know any more such examples? Are any of these examples of gaol slang entering normal slang or at least youth jargon?
How about the slang term for money? Which is your favourite: szmal, forsa, kasa, dutki, hajc...?
Know any others?

mamona, kapusta, szmelc ;)

'Siema' is a trademark word of Jurek Owsiak

The others are used by older people who think they sound cool and young when they use it, or by youths who think using slangy words will make them cool. I think 'spoko' is entering more common speech. Sometimes I use it, but never in formal situations. I guess these words sound a bit... ridiculous. I'm 22, so I guess I'm still a youth, but if someone started talking to me like that, I wouldn't treat the person seriously.

Only Jurek Owsiak can say 'Siema!' and not turn out silly. :)