Revenge is a dish best served cold, but honestly, I think that phrase could be reworked depending on the individual to "revenge is a dish best served petty."
I know the word petty gets a bad rap, and it's because petty people are usually just the worst, always arguing about the way the bill's split up or bringing up gas money while conveniently forgetting all the times you hooked them up.
But sometimes, you just need to get back at somebody without causing a big stink. Now that could be a form of vengeance that's surreptitious. Maybe someone doesn't know you let the air out of their tires? Or put a few pebbles in their shoes, preferably under their soles, so they walk a bit before they get so uncomfortable they have to take their kicks off and shake the rocks loose.
Whatever your form of petty revenge, sometimes the passive aggressive, small-scale approach gives you more satisfaction than letting someone know you were the maestro of their demise, the architect of their doom.