It only took me three and a half years, but I finally got 100% completion for Grand Theft Auto: San Andreas. Even using guides it's still hard for me to find all those hidden items. So what's my reward? Well, I got some stats maximized, although I'm not sure which ones, I also received a Rhino tank and a Hydra plane near my Ganton house. They put the damn plane on top of Sweet's house, and I can't get up there without a vehicle to stand on. Nice reward.
I still don't have max weapon stats, haven't done all the unique jumps, hate burglary missions and don't date any of the girls, but it's nice to know there's still stuff to do in this game. What an incredible amount of content. If GTA IV is anything close to this, I'll be thrilled beyond belief.