So many I haven't tried! And so many I never will. If I were guessing which would be my fave had I tried them all, I'd go with amphetamines (minus meth...ick) and OxyContin. And I'm sure heroin's just GREAT, but I'll be damned if I go there in this lifetime.
Of the stuff I've tried, I'd say hydrocodone, weed, and ephedra are my faves...hydro for its lovely euphoria, weed for its mild psychedelia and deep thoughts, and ephedra for its intense stimulation. As much as I love opiates, I think I'm an upper girl at heart, being so low in energy and enthusiasm due to depression or fibromyalgia or chronic fatigue or whatever the fuck is wrong with me lol.