When the Dreamcast came up, my school took us on a field trip to a museum that detailed the history of video games and you could play all consoles.
There was a game in the Dreamcast about a guy with a drill, and you had to drill your way down to the finish line. It was sort of an inverted Tetris.
Anyway, that game was cool because even though it was simple, it was challenging, and out of a whim I decided to waste my turn putting the challenge level in Expert. And I won!
I had been clutching the control for like seven minutes of non-stop running from a mine collapse and my friends couldn't believe I beat the game in my second try. :P
Other than that, I had my little own Battle of Termophylae in Total War 2.
I had a small army of about 400 troops in Frankfurt, although they were my best troops, and the damned backstabbing French attacked Frankfurt with three full armies.
I saw the little window that comes up before a battle telling you the number of units each faction has (400/8500 I think) and it tells you how much of a probability do you have of winning, and I was surprised that I had like 30% chance of winning.
And I won.
Completely obliterated the French. Now in my campaign I rule all western Europe.
Damn, that was awesome moments, not bizarre moments. But I'm sure as hell not erasing all I just wrote.