I few weeks ago I had the idea for a LCD-based (instead of rastered laser (SLA) or projector (DLP)) 3D printer. I was enthused to discover that I'm far from the first person with the idea. I was also pretty bummed to see that there don't seem to be any committed ongoing efforts to delivering such a device. I don't see any fundamental reason why it couldn't be as good if not better than SLA/DLP.
I will summarize my findings here (in order of hilarious to disappointment):
1) (Hilarious video)
This would be cool if it existed...but I don't think it was realized as a product.
2) (Pretty funny, epic soundtrack)
This looks like a promising early prototype. Would love to see more.
3) (Not very funny)
Looks like these guys started thinking about this for long enough to make a 1 page website and then gave up...oh well.
4) (Super disappointing)
This Kickstarter for the 'ibox nano', a LCD 3D printer, has raised a lot of money and currently has a lot of angry followers (judging from the comments).
Ok, on a more serious note, here are a few additional resources via this thread on BuildYourOwnSLA.
Some papers describing LCDs for this purpose in a bit more detail ("active mask lithography":