Mine, too, I think.

Being one of the top server tanks 2 weeks after WOTLK hit.

Getting into Nintendo Power for a Rogue Squadron challenge.

Also, beating Goldeneye 100%, and obtaining every cheat.

I dunno, I'm not that good of an achiever, but let's see, I'm proud of:

-Getting 881m (and some cm) in the moon stage in Katamari Damacy, and 3631m (I think it was that number, more than 3600m for sure) in the elephant stage in We Love Katamari. Also, I got a perfect 10m in the North Star in my first try in the first game

-Winning the Premier League two consecutive times with Manchester City in Football Manager 2005

-Beating Shadow of the Colossus without any single help, there were times I wanted to check a FAQ because I was getting desperate, but I had promised before beginning the game that I wouldn't check anyone, so I didn't give up. It was well worth

-Beating Tony Hawk 3 (all the objectives from all the levels). I know it's not hard , but I'm not that good in that game, so I'm very proud that I beat it (then I beat it some times more)

holding the speed-run record in resident evil 4(gc) for 2 days.

having every pokemon in  pokemon red(got that diploma b"+ches) and a all level 99 team

always won the smash tournament in my district(in the netherlands) total;15 times, after that i just played but always passed in the finals.

playing superman 64, and didnt burn the cartrige.

Playing through Sonic '06 and actually watching every cutscene from beginning to end. God I hate Elise.

I'd have to say beating Super Mario 64 with all 120 stars. What a great game.

Beating the very first TMNT game on NES, dam that game was hard. 4 lives and no continues, wasnt too hard til i got in the Technodrome then it just started to get insane.

Back in 1987 I got the nes for christmas and the legend of zelda. I beat the game several times and got so good at it, that one time I beat the game without losing one life.

Somebody here said something about Ocarina of Time Water Temple? That was the part where I stopped playing that damned game. Been afraid to touch it again ever since.
It`s realy hard to remember everything I ever did. I remember it was realy hard finishing Hagane on the SNES. Turrican 1 and 2 were also hard as hell. The last of the challenges of the Gods in God of War was pretty hard too. Did anyone else find the Hades Paradox Cup in KH2 realy hard?