FLCL, literally watched it more than the current episode count of The Simpsons. Seriously... o.o Another series I watched the hell out has to be "Panty and Stocking with Gartnerbelt." Probably like... 15 times on a season rewatch.
ive seen a few episodes of lucky star multiple times, maybe 20+. I could even remember them word for word.
I have never rewatched a series tho and hardly any movies since im "cursed" with an above average memory which imho sucks since you never get value for anything since it gets boring to watch thing u already know everything in.
I have lost count the amount of times i have watched Neon Genesis Evangelion, ive seen certain episodes probably around 20 times or so, same with End of Evangelion.