The best legal thing I ever found to get fucked up on is salvia. It's nothing like getting stoned or drunk or tripping... it's a mind numbing disassociating five minute roller coaster ride to nowhere. Although it does give one a bout of insane laughter, which is kind of fun. But seriously, it is something worthy of trying at least once.
www.iamshaman.com sells salvia. If you get some, go for the 10x extract, the non standardized 10x one is what I tried and boy does it fuck you up. You have to hit it with a flame the whole time you toke and hold the smoke in as long as you can. Bong rips are the best way to do salvia. By the time you exhale, you'll be on a salvia trip, which is fucked up and will render you incompetant and unable to do anything but fall over laughing for about 3 minutes. Then reality will slowly reassimilate itself as your ride ends.