Besides the obvious of Pink Floyd & Led Zeppelin.
I also feel the same way about a Damn Yankees reunion. I didn't think there was that many other people who wanted one too. (Actually I've had a theory that Styx should take a year off. Tommy could reunite Damn Yankees for the year. Dennis can finally release 100 Years and tour to support it, and JY can take the time to realize that it WOULD BE beneficial to reunite the original line-up; it The Police can do it, so could they!)
Also, at some point, Van Halen with Sammy Hagar. I am NOT saying I hope for this period with Roth to end in the least. (Saw them at MSG and they KICKED ASS). I just would like to see them with Sammy (with Eddie in good health) at some point in the future).