The Sims 3 Install Helper Monkey
The Sims 3 Install Helper Monkey is a sweet little tool that will “automagically set up your game so you can use custom content .package files for The Sims 3″.
No more worrying about creating files or getting yourself all worked up about whether or not you put your stuff where it should go.
Keep in mind though that it doesn’t install .sims3pack files since the game will do that for you.
All in all, this is a pretty helpful little tool [hence the name] and is practically guaranteed to make your life easier.