You know that many guys dream of having a super sexy girl, who would please them in the most possible and impossible ways. So show him your newly acquired masters degree in sexology and he'll feel totally lost.
You may also challenge his jealousy by starting dating the guy he always jealously suspected you were having an affair with but weren't.
When picking up your things from his house, break a remote and set the parental controls on his cable TV to lock out all sports and erotic channels.
You may spread the word among single girls that a certain guy you used to date doesn't believe in foreplay. This will definitely kill his confidence in his sexual power, which will make a perfect revenge from your side.