I just got back into a regular lifting routine about 3 months ago, and have seen moderate gains in muscle mass/ power. I am not looking for a quick fix, but have been considering creatine. I had some roommates a couple of years back (2001) that used it and had definite results. I stayed away from it b/c I didn't know if there were any side effects. Most of the research that I have done doesn't really mention anything except for possible kidney problems. Does anyone have any bad experiences with creatine?