By using the filters from a pair of RealD 3D glasses from the cinema you can easily create your own 3D Home cinema. I happened to have my old projector lying around after upgrading so I thought I'd demonstrate how simple it is.
RealD 3D glasses are circularly polarized so to make a home-cinema that works with these glasses you also need circularly polarised filters for your projectors. By opening up a pair of glasses you get two filters for about a buck. (If bought at the cinema.) Place each filter infront of the projectors so that the light shines out through them as if the light was shining out of your eyes. When viewing, you wear the glasses normally so the light passes the other way through the filters.
I recommend you use a program like Stereoscopic Player from 3dtv to display a test-image on both projectors for alignment.
It's this easy. No magic, no expensive stuff. (Except that extra projector ofcource.)
Oh, and you need a video-card with dual-monitor support.
One thing I forgot to mention in the video: You need a silverscreen or a reflective screen. Regular white will not work. The reflective surface will allow the light to return with the same polarization as the projector gave it so it is absolutely essential. If you already own a screen that is somewhat reflective for daylight viewing then it should work.
