For aerial moves, very little compares to what TAKA Michinoku does in one match on a comp tape I have. His opponent is outside, near one of the corners. TAKA runs towards him and jumps up onto the top rope to do his crucifix plancha. As he does, his opponent grabs the ringpost and swings around the corner of the ring, out of harm's way. Without missing a beat, TAKA bounces off the rope in front of him, lands on the other top rope to his side, and jumps off it to hit the crucifix plancha. Jump, bounce, DEATH FROM ABOVE. It was frickin' BEAUTIFUL.
More obviously telegraphed, but still really well-done, was a spot at the end of one of the best trios matches I've ever seen, a Michinoku Pro match. Jody Fleisch was going for a plancha, Curry Man was in the ring with him. As Fleisch hops up onto the top rope for the plancha, Curry hops on to the second rope, grabs Fleisch, and Rock Bottoms him back into the ring (where he then hit the Spicy Drop for the win). Kicked ass.
Speaking of Fleisch, I was there when he nearly DIED getting an almost-botched Ki Krusher '01 from the top of the ringpost. That was an adrenaline rush, but in a bad way. The same night, I marked out when Hotstuff Hernandez, who is at least 6'3" and 350 pounds legit, hit a picture-perfect tope like he was ReyRey.
For non-aerial stuff, well, there are tons of moves that make me go "damn!", but I think Super Dragon's Psycho Driver (torture rack into piledriver) and Slugger's Body Bag (dominator into an Emerald Frosion-style headspike instead of a face-first bump) are consistently near the top.
And if you'd like to check out insane moves,
check here. (It'll ask for a password, but it tells you right in the dialogue box what to put in.)