Fringe finale
I've thought since the series started that it reminded me of several works of Warren Ellis, especially "Planetary". I find that even more so now.
Leonard Nimoy is obviously great stunt casting, although he didn't actually get to do anything. Hopefully he'll have a meatier role next season.
Olivia, who was the show's biggest weakness when the season started, has evolved for the better, so that's something that has worked out.
My interpretation of the tombstone scene is that the 'real' Peter is dead, and Pacey is the Peter from the alternate world. That could be interesting to see play out.