I've tried caffeine. All sorts of medicines for various temporary illnesses.
But in terms of recreational drugs, I've smoked tobacco and weed and drank alcohol.
Tobacco, I partake in only once per year in the form of a New Years cigar with friends.It's not really my thing but it's not entirely unpleasant and a cigar is nice to commemorate an occasion now and then.
I smoke weed probably about 3 times a week. I have no intention to stop. It's relaxing and much less destructive than the majority of other recreational drugs. (No, I'm not claiming it's "not a drug" or does not have any risks associated with it; it does, just fewer.)
I used to drink occasionally. Two or three times a year at geeky parties and such. However, it's no longer worth it to do so. I got most of my stomach chopped off half a year ago and now my tiny baby stomach can't drink enough for it to effect me in any way unless I go for hard liquor, which is absolutely distusting (in my opinion). xP