Slang no. 1: Sup
Meaning: Whassup, hello, how r u?

Slang no. 2: Srsly
Meaning: Seriously

Slang no. 3: TMTH
Meaning: Too Much To Handle

Slang no. 4: Fo Sho
Meaning: Definitely, certainly

Slang no. 5: PIR
Meaning: Parents In Room

Slang no. 6: Fly
Meaning: Cool, happening

Slang no. 7: Subprime
Meaning: Substandard

I find most of these slang very ang mo, very western. Other than the 'sup' n 'srsly', dun think the rest will b much use in Singapore. Not local enuf i can say. For example 'TMTH' can b easily replace by our 'bth', short form of 'buay tah han' hokkien term for cannot take it. 'Subprime' is also replace by 'cmi', meaning 'cannot make it'. I still prefer our own local slang. =)