Touchless Orgasm

I've heard that it's possible for a bottom to get an orgasm without having his penis even touched. Has anyone out there been lucky enough to accomplish this themselves or make it happen to their bottoming partners? Supposedly, the prostate is the male g-spot, and with proper stimulation by the penis and the right position, it IS possible to have a "touchless" orgasm. I surveyed a couple gay couples that I know, and a couple of them actually told me it has happened for them. I am amazed. Ha ha. If you know how to make this happen, please tell me (what position, etc.) I am sure other inquiring minds would like to know as well.