Twenty dollars worth of cocaine.
Lets pick up a couple twompers and hit the bars.
What seriously stupid people call twenty dollars worth of weed. Some not quite so retarded synonyms would be, a dub, dub sack, twenty sack, etc.
David: Lemme get a twomper yo!
Jon: No, you're a fag.
David: Seriously, hook it up.
Jon: No seriously, you're a douchebag.