Well I'm down to two achievements in Sims 3 thanks to a glitch in the game that lets your money keep going up by replacing your house and selling off cars. Found it over on TrueAchievements. When I got the 350,000 dollar house achievement, I also got my 150 challenges complete as well since I was only one away from completing it.
So now I'm down to "Earn a Lifetime Wish as a Young Adult" and get "1000 Wishes". I've already adopted a child, aged him once, taught him to potty, walk and speak. So now when he ages up again, then I get to pick his traits and go for the Lifetime wish with aging turned off.
The 1000 wishes however is going to be a grind. With my wife having played the game and me, I'm close to 700 wishes now. No telling how long it'll take me to get to 1000. So it'll be just playing the game until it happens and try to get as many wishes done as fast as I can.