This is an attempt to not take away from the "Da Mega Mans" thread, but still shamelessly plug my video reviews. Mega Man 3 was a great third game to a series. It wasn't quite as good as Mega Man 2, or maybe it was. It's really debatable. Super Mario Bros 3 is clearly the best one in it's respective series. Mega Man X3 was nowhere near as good as the first X game, and still not as good as X2.

What other 3rd games or trilogies can you think of?