Here's mine:
- Assassination Classroom
- Daily Lives of HighSchool Boys
- Nichijou
- Fruits Baskets
- Kaichou wa Maid-sama
- Ouran HighSchool Host Club

There are so many anime that I would like to watch but the ones I re-watch the most are:
1) Code Geass (I watched this 3 times in the past month hahaha)
2) Samurai X (This was the first anime I ever watched)
3) Prince of Tennis
4) Major
5) Hungry Heart

Brain-Splattered : Re-watching good anime is what I now do in my spare time since I don't really enjoy the newer ones. I used to re watch a lot of CLAMP shows, I would re watch the first half of FMA so that I could start on the second half of FMAB (cause the first half of that show just didn't get into as much depth as it did in FMA). Any show that has an intricate storyline is very re watchable for me.

I've only ever re-watched Zero no Tsukaima, because years had passed since my first viewing. With time, I suppose.




By that logic, I guess I should re-watch Chu-Bra.


Nope.

I've seen Hellsing Ultimate I think 2 or 3 times. I've rewatched Yu-Gi-Oh! two times at least. At least the first 2 seasons. Plan on rewatching Ayashi no Ceras sometime. 

I really like rewatching DBZ episodes. That's an instant classic right there. There aren't many other anime I've gotten into as much as that one.

I'm not sure which ones people would freak out over so I'm just gonna post the anime I have rewatched in the order that I rewatched them.

Arakawa Under The Bridge
Zatch Bell
Arakawa Under The Bridge
Naruto
Strange+
Arakawa Under The Bridge

(Arakawa Under The Bridge is obviously my favorite).

I think the only anime I rewatched which was purely for nostalgic purposes is the first season of Pokemon which is probably the one reason I would completely rewatch an anime (I've done the same to some extent with Yu-Gi-Oh!, Digimon and Beyblade but that was long ago and not whole seasons). I used to rewatch the first episodes of Pokemon specifically a lot as well when I was younger since I had them on VHS (saying that somehow makes me feel old lol). Otherwise I'd rather spend time discovering new animes/tv series in general etc or just doing something else as I'm not as big of an anime watcher anymore.

I have rewatched individual episodes of others or restarted it if I wasn't too far in with animes like Naruto, Bleach etc, though that was more for convenience because of not having watched them in a long time and having lost track of which episode I was at, due to how many episodes those animes consist of, also helps with remembering the plot and the background to an episode if it happens to resume at a cliffhanger or something of the like. I've also rewatched some scenes, epic fight scenes since those are entertaining like the one between Ichigo and Byakuya or Naruto and Pain.

So I went back to watch to watch some blue excorist after listening to the song and posting it up in a thread.  I watched naruto again I purposely went to watch the fight between naruto and neji since that was one of the best fights ever. There are others but that is my personal favorite of all time. XD