Shard wagon 

A vehicle which tweakers drive around while high on meth (usually a later model peice-o-shit with chipping paint)

Oh here comes kyle on his shard wagon...

I can't get in that shard wagon there's girls around...

Shard wagon by smile your gacked December 6, 2010

Shartwagon 

Verbe: The act of farting in an inescapable enclosed area. (i.e. an elevator, or car in motion)

Noun: An alternate term for a Douchebag

1) I just turned this elevator into a shartwagon ride to the penthouse

2) Its gonna be a long ride to the jam-basket in this shartwagon.

2) You are such a Shartwagon

Shartwagon by Shartwagon September 2, 2010