Kava Kava for social anxiety and depression
Kava Kava is a plant native to the South Pacific which, when prepared as a tea, has a similar effect to alcohol and nicotine, but without the danger of addiction. You can buy it in a powder, an extract, or in pill form, but I suggest the extract just because I like the taste of it and it's easy to prepare. The taste is pretty strange though, so if you don't like it you can go with the pill form.
To be a little more specific about the effect, it kicks in very quickly and comes on as a mild intoxication and light euphoria. This effect lasts about a half hour to an hour and gradually fades into a tiredness and sense of well being. Overall, it makes you more talkative and social, less anxious, and generally happy. It is a lot like having a couple beers and smoking a cigarette, but without all the health risks.
One thing to note is that when buying it, make sure the stuff you're getting is derived from the root of the plant ONLY. Some companies will use the bark as well to cut costs, but the bark has been linked to liver diseases. The root on the other hand, is completely harmless and has been used by natives of the South Pacific for hundreds of years.