Like SomeDude said the best revenge is living well.

Nothing says "Im mad at you, I care, and I think about you constantly!" then getting revenge. Are you trying to feed this person's ego or do you really want to get back at the person?

If you really want to get to a person than act/be unaffected by them. I'll give you an example:

When my husband and I were dating we broke up for a little while (against my wishes) so to get him jealous I flaunted men I was dating in front of him. His reaction? "Glad you're having fun." or "It's nice you're getting out there meeting people." Always with a pleasant smile. He was not going to let me get the best of him or show that he was jealous. I was furious.
I wanted him to get jealous! Scream, yell, beat somebody up, or flaunt another woman in my face. At least then I would know he cared and I would have felt important. His indifference infuriated me more than had he had a bad reaction.

I found out later when we got back together that he was very jealous, but he said he was not going to let me know that. And he did a damn good job of not letting me know.

Anyway, I reinterate - Do you want this person to feel that they must be important to you...or unimportant to you? A bad reaction to whatever they have done to you will only feed their ego and what's really likely is they'll find you laughable and/or sad. It absolutely won't make them feel that they've been put in their place. No matter what great revenge you come up with.
Seriously, live well.

Just my 2 cents.