wanksta
Ever see those little rudeboys who walk down the street threatning everything they see, thinking there hard, until some big bloke walkes past, he gets called then bang...the kid walks off back to his pregnant 20 yr old mum and his smackhead stepdad...(thats the english way :P)

Or in other words, some twat who thinks dey hard...
little twat: Oi ya bastard, ya fuckin startin?
big guy: No...
little twat: Yeah ya are, cmon ill knok you out
big guy: Stfu u wanksta