Well, without the help of drugs or alchy I've used mind shaping exercises and nuero linguistic programming. I really wanna do that isolation tank thing, I hear good things about it especially when your on shrooms and take the plunge. It's $75 and hour in San Fran though and I ain't balling yet.
sleep paralysis. google "wake induced lucid dreaming" to have an out of body experience whilst totally sober laying down in your bed. Expect to hear extremely loud explosions.....
I have done a lot to alter my consciousness in the past. Then I realized the problem with the world was too many people walking around in an altered state of consciousness (whether drug, media or religion induced). It's strawberry fields, where nothing is real, and nothing to get hung (up) about... Strawberry fields forever.
How about the passing out-choking-masturbation game. That's how the lead singer of INXS, Michael Hutchence, died... supposedly.