There are a number of things I've never seen in hetero or homosexual porn. They may be out there somewhere, but the fact is they should be on my computer or in my bedroom instead! Here are two of them!
1. A D.V.D.A. (double-vaginal, double-anal) penetration. A number of pornstars including Ron Jeremy claim to have partaken in this Holy Grail of porn but I have never come across (literally or figuratively :) ) any video or pics of this act.
I can only imagine two ways in which it could be achieved. One is that 4 men all lie on their backs in a star formation, their legs interweaved and their cocks all as close together as possible, pointing straight upwards. The woman, naturally already fully loosened up, comes and squats on them, putting two in her pussy and two in her ass.
The second method which Ron Jeremy described was to have three guys of normal length cocks and one of extra long. One lies on his back and is mounted by the woman in standard 'on-top' style in the vagina. The next chap straddles her ass with both his feet on the left hand side of the prone couple's bodies but his cock in her ass. The next guy does the same on the right hand side of them. Finally, the guy with the huge cock comes from behind and does a standard vaginal penetration position.
2. I don't know a name for this next position as I believe I made it up, but I've never seen it done either :) This could be done by hetero, bi or homosexuals as you could swap in the men for women with strap-ons as required.
One person lies on their back flat out. The next sits on their penis/strap-on in standard 'on-top' position. The next comes and sits across the stomach of the person lying and is entered by the person behind them. Now, depending on how many people you want, you could end it there with the person lying down sucking on the genitalia of the person sitting on their stomach. Alternatively, you could add in yet another person, sitting over the upper-body/shoulders of the prone person, and have them entered by the person sitting over the stomach. Finally, the person lying down can lean their head forward to suck the penis/vagina of that person.
If anyone can find any pics or videos of these acts, I would love to see them!!!