I like Hydroxycut. It's pretty potent, so just as a warning, I strongly reccomend that you slowly increase dosage as per the bottle's directions. The only thing to consider if taken in conjunction with creatine is that creatine will hydrate your muscles and ephedrine/caffiene will dehydrate you. Since they kind of counteract eachother, I would recommend cycling the two alternately (maybe 4 weeks on/off for each) but there aren't any health risks that i have heard of.
Keep your body lean, your blood clean and your mind sharp. -Rollins