It depends on what you want to use to playback your movies. An htpc or a hardware 3d blu-ray player. Using a computer will most likely be the best way but maybe the most expensive. The type of projector to look for with both input plugin types is "hdmi 1.4a" and "vga" or "dvi-d" branded 3d-ready with optional dlp link glasses going at "120hz" at native resolution. Now you can get projectors that have a native resoltion at somewhere like 800x600 BUT, I'd try and get something in 720p 120hz 3d ready. Acer has a good selection and also Optima, maybe even benQ.
If your going to only use vga as a stereo3d connection then you will have to use a computer htpc with blu-ray drive and stereo3d playback software and at least a quad core cpu or a compatable mvc codec hardware acceleration gfx card.
If you get a projector with hdmi 1.4a input, then you could connect a playstation3, standalone 3d blu-ray player and a computer using the framepacking format.
I think some projectors that have hdmi1.4a and vga input on the same projector, will allow you to use both connections for stereo.
2x Amd phenom ii x6 1055T
Asus Motherboard DDR3-16GB
Microsoft x6 keyboard - x5 mouse - vx 3000 webcam
Soundblaster Hs-1200 headset - 900mhz headset -voice buddy
3x 5.1 audio system, sony, yamaha, logitech
Acer H5360 3D-Ready Projector
2x 32 inch 60hz anaglyph1080p workstation monitor/tv/gaming
Nvidia 3D vision Kit
3x dlp link 3d glasses
Edimensional wireless glasses, 2x wired glasses
Nvidia Gtx 670 superclocked 4 GB
Nvidia Gts 450 ddr5 OC 810mhz 1024 GB Physx card
Ati 6450 1GB Workstation/Internet
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JVC - Digital SD Camcorder 800x zoom
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Windows 8 x2waiting for autostereo cubed pixels displays