Triple-Lensed Analog Camera for Stereo Imaging
The "120 Tri-lens Stereo Camera" seems misnamed at first—why would you need three lens to take a stereo image? Turns out you don't. The top lens is for sighting.
No price yet, but considering this is a completely manual film-based camera, I would imagine those of you interested in stereographic images are already used to paying a premium for your equipment.
Tricloptic SLR Camera Only Takes Bicloptic Pictures [OhGizmo]

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This is great! I take a lot of anaglyphs and this would really make things a lot easier. I just wish they'd make a digital version already!
Another approach might be to buy a couple of Canon cameras and hack the firmware with this open source software:
http://chdk.wikia.com/wiki/Downloads#SDM-CHDK_.28StereoData_Maker.29
I don't use CHDK for anaglyphs but it also adds features like time lapse (via a macro language), RAW, auto bracketing and extended exposure times to my lowly Powershot 710.
Not to be too nit picky, but it isn't an SLR. As you can't look through both lenses (well, not easily anyway) the third framing lens allows you to focus and "see" the same thing the stereo lenses are. So it functions the same way as a TLR (Twin Lens Reflex) camera does. A Rolleiflex, for example.
In this case, I suppose we could call it a Tri Lens Reflex . . .
Designer 1: So why'd you put three lenses on it?
Designer 2: Well, it's "Three-D," innit?
Designer 1: Go design another toothbrush.
I contacted the company about a year ago when this product was first announced. At the time, they wanted 9800 Yuan (around $1400 today) for it.
Oh, here's a retailer that has it for $1600.
Not really worth it since you can get a pair of used Bronicas with lenses for less than half that these days.