Revenge is bitter sweet. I was tagg'd along for two years until I found out my ex had cheated on me with 3 separate blokes, and was chasing 1 for a more intimate relationship. Apart from telling her the four letter word, I poured sugar into the gastank of her car. Apart from the obvious damage (caramalising the engine, requiring an entire engine rebuild), she lost her job (couldn't get to work), had to defer uni for another year (she had no car), screwed up her family (her mother was pissed she had to support her again - AND pay for the car), and generally isolated her even more than she had been (she ditched most of her friends when she left school (year older than I was).
The final icing was when the guy she was chasing told her to fuck off also.
DO NOT TAKE REVENGE LIGHTLY - IT IS A DEADLY SERIOUS MATTER AND SHOULD ONLY BE EXACTED ON THOSE WHO REALLY DESERVE IT - looking back, mine was probably overkill (because of the chain on effects), but I believe in the end, it was equal payback for two years of heartache (wondering why she didnt call, seem interested at times, etc - and then be over me like a rash).
In conclusion, if your after a good guide, look for both the Anarchist's Cookbook (find one of the newer editions) or The Avenger - both are freely downloadable ebooks.
Anyway, Im off
Cheers
Camm