Not much. All I really use is Whey Protein from Kaizen & Scivation + a multi-vitamin. CL's Orange Triad costs me $35 every two and a half months, the protein costs me $30 - $60 depending on if I go with the 5 lb Kaizen or the 10 lb Scivation.
Used to go all out with pre-workout stuff, creatine, test booster, etc,. Just not really worth it, imo.