In order of importance:
3. Protein supp.
4. Creatine supp.
5. Sometimes a fish oil supplement if I get achy joints, which isn't often
The effects of everything else are so insignificant, they're not worth taking, IMO. The supplement world is a business...they're going to tell you that you need BCAA's, aminos, ZMA, glutamine, CLA, beta-alanine, HMB, fat burners, tribulus, CGT, L-Carnitine, nitrous oxide, a multi vitamin, thermogenic crap, etc.