I'm an INTP and recovering opiate addict. I rarely spent/spend money on anything other than depressants (opiates, benzos--currently in suboxone treatment, though that's about to change due to a lack of insurance), though I do enjoy throwing a little coke into the mix, and I still enjoy smoking pot and taking hallucinogens given the opportunity. I'll do anything if the price is right, though. One of my good friends is also an INTP and recovering opiate addict. My ex-girlfriend was an INFJ and psychology major, which is the reason I know my personality type to begin with. She wasn't an addict, but would use various drugs on occasion (mostly when she didn't have to pay for them, lol). I think it's a safe bet to say that most of my friends are introverts, and that most drug users probably are. This, IMO, is simply due to the fact that introverted people enjoy the taste of extroversion drugs like opiates, cocaine, alcohol, etc. can give them. The affinity for opiates is interesting, though. Perhaps it is due to a combination of introversion and depression? Drug preferences have always interested me, as certain drugs I downright dislike (mostly the more obscure ones, but I hate coming down off of stimulants, and not being able to sleep, etc.), while others I find the idea of using them every day to be rather impractical/unappealing, though I guess being dope sick all the time really isn't all that "practical" either, but at least it seems that way in the beginning, before it's too late. Interesting thread. Oh and, for whoever is interested, I forget the name of the test, but I also remember having trouble deciding whether I was a "personality type 6" or "type 9" based on the results of another personality test that my ex had me take.