This one takes a little muscular strength and tenacity, but it can provide surprisingly enjoyable results. In particular, I find that this technique both extends orgasm length and significantly increases pre-orgasm pleasure.

Begin by lying flat on your back. Start to masturbate. When you reach a point where you're completely aroused but still a ways from orgasm, lift your legs several inches to a foot into the air. Actually, a lot of times I find it easier to lift my head and chest a few inches as well, so that I'm balanced entirely on my butt. What I find is that the pleasure of masturbating usually increases immediately when I go up into that position. If I'm lucky, sometimes I'll hit that wonderful point where I feel like I'm on the verge of an orgasm, but it will last for anywhere up to a minute before I actually come.

This one has given me some of the best orgasms I've ever had. It's not complicated, but it takes a surprising amount of willpower and concentration.