It's not exactly optimal for home theater or anything, but this 84-inch rear projection "dynamic digital signage" from NEC is, well, big. The WT600-DS84 has only a native resolution of 1,024 by 576 pixels (although it can fake it up to 1,920 x 1,080), but did we mention it's big? No idea what sort of prices we're talking about - it's available only through special dealers - but I'm sure we're talking a fair chunk of change.
I think the best part, though, is just how thin it is. It's hard to hate wall-mountable anything, even if the resolution is crap. (Thanks, Marleen!).
Product Page [NECVisualSystems]