Well, aside from the almost obligatory cannabis there has been:
-Cocaine (Awful time. Didn't like myself on it at all)
-Mephedrone (Horrible stuff, again didn't like myself on it)
-MDMA (Wonderful, provided some of the best nights of my life)
-Speed (Used to use this to keep up with work. Now I just drink coffee, which is much better for me and my wallet)
-DXM (Gave me a really sore throat, probably due to the method of ingestion. Had an OK time but not rushing to do it again)
-Shrooms (Awesome stuff. Did it around a fire with some mates at a festival. Great night)
-Mescaline (Crazy stuff. My fireplace spoke to me and all sorts of mad sh*t happened)
-GHB (This one was a spur of the moment thing at a festival. Did not realise that mixing it with alcohol is incredibly stupid, felt so awful for about 3 hours -- rough as f*ck)
-Ketamine (Did this to go into a hole just to see what would happen. Really enjoyed it but haven't done it since due to not wanting to build a tolerance)
And then there's the herbal stuff and the legal highs that either work or don't. My use tends to fall into 2 distinct categories. I'm either in a club or party setting or I'm just with some mates and want to relax and wind down. But moving to a new town has knocked my use on the head for a while as I'm just knuckling down and trying to work for a year or so. Plus I was building up a hell of a bill and a hell of a tolerance to my favourite things.
I don't really have a wishlist either -- although I would like to try LSD and some cannabis edibles at some point. And I can see myself revisiting quite a few of the drugs from the above list in the future because some of the nights that they've given me and my mates have been incredible.
And to expand on what orbital said, it really is no fun being the only guy who's out of it on something in a club. You may not care at the time but the embarrassment of waking up and being the only one with no cheeks, an aching jaw, and a huge headache, is often not worth it...