Personally I don't believe in OBE's. Here's a long, but interesting read...

http://lucidity.com/NL32.OBEandLD.html

Not that you asked me, but I get SP by staying conscious until it happens. It's not something I can induce, but it will happen eventually before you dream, so if you can stay conscious until then, it will happen. Tough to do though, as I often fall asleep trying, or give up waiting (and then fall asleep). Of course you can't stay awake from the beginning of the night, so WBTB method is good to use.