Smart Sleeping

I have been looking for a utility like this for a while.

Mac laptops have a strange way of sleeping. Unless the battery is close to being completely depleted they will just go to sleep as opposed to hibernate (by hibernate I mean that the contents of the RAM are saved to disk and the machine is actually shut down.) While this may see like a good idea, it does not work well if you want to change the battery without having access to power as the Mac does not go into hibernate mode in a predictable fashion.

So what I have been looking for is a way to make my Mac laptop go into hibernation predictably and I think I may have found it. SmartSleep is a control panel which allows you to control if and how you Mac laptop goes to sleep and/or into hibernation.