Marijuana, on the other hand, has almost always made me temporarily psychotic, or at least paranoid. It's also very safe physically. I'd be curious to know about any decent rationalists' attempts to "beat" this or other drugs.

I can easily "beat" alcohol (i.e., think and act the way I would if I were sober -- modulo motor impairments) if I want to (unless it is so much as to make me sick). I no longer smoke marijuana that often these days, but the only time I did after finding Less Wrong, I felt like I didn't want to beat it. I'd have to resolve to try and beat it before smoking it, I think.