Well, I don't have much to brag about, so I'll also list the things I should be ashamed of in my games. :)
Achievements:
1. I completed the Hoenn Dex. Not that exciting.
2. I've caught a couple of shiny Pokemon. Drowzee and Gulpin, to be precise.
3. My Level 51 Lapras grew to level 92 while I was working on my Hoenn Dex. I know that's not that impressive, but what if I told you that during those 41 levels, it never gained more than half its experience in every battle? I used it to do the fighting while other Pokemon gained half its experience with Exp. Share. (Again... not too impressive... but it sure requires a lot of patience... since Lapras requires as much EXP as a typical legendary)
4. I beat the Elite Four over 100 times in Crystal.
Things I'd Rather Forget:
1. I ran into a shiny Xatu in the Safari Zone in Emerald. And... it ran away!
2. When I first played the Red Version, I killed off Moltres thinking it was a common Pokemon.
3. When I first played the Red Version, I used my Master Ball on some random Pokemon on Route 1.
4. In the Crystal Version, when I fought Suicune, I killed it, thinking I'd get another chance to catch it. Nope!
5. I ran into a shiny Poochyena last night. Unfortunately, it was very early in the game, so early that I had not gotten to the point where you received your first Poke Balls. So I couldn't catch it. ;-;