Does Creatine Work?

I have been trying to find out about what sort of supplement that i should be using if I want to get the most from my workouts at the gym. It seems that creatine is the the most successful supplement that I have found. Though it is only helpful for explosive sports such as sprinting or weight lifting not for endurance. I did a little more digging and it seems that creatine can also help with neuromuscular diseases, helps fight the aging process and assists maintainance of antioxidant status. It all sounds too good to be true!! Is it really as good as all this? Does it really work? Is there any negative side?