When did intentionally bad smelling become cool?

Serious question, when and how did this very popular trend start?

I see it every where; comment sections, forums, the other day I was playing chess on the iphone and my opponent wrote 'haven't showered in days' to try to throw me off my game.

It was cool when that one hick wrote 'I smell like ass' on that sign. But it is a little played out at this point.

It's not. But BoobySak thinks it is.

Hippies have smelled bad since what the 70s?