In Star Wars Jedi Outcast II: Jedi Knight, the final cutscene between Kyle Katarn and Desaan. I know it off by heart, it's so spice.
In Metroid Prime, when you first enter Phendrana Drifts, or that first hour in Phazon Mines. Or the trouser-wettingly terrifying darkness of the Phendrana Research Centre, with all the Metroids popping out everywhere.
In Age of Empires II, when you're running a huge fortress of double walls, airlock gates, with Aegis on, and knights and castles popping up everywhere, and the constant scream of champions falling to the constant barrage of bombard towers and mangonels.
The music scene at the end of
LA, when you're on top of the world and all eight instruments are playing in perfect harmony... Aw, it's taste.
When General Carter is executed in Advance Wars: Dark Conflict. It made me all teary-eyed. Or when I re-enacted D-Day with at least ten landers and a fleet of battleships. That was good too.