With the upcoming Nintendo 3DS, I've been wondering why there aren't TV screens that can produce 3D with out the use of glasses. With that said.. the challenge is to have a TV that can do 3D with out the 3D glasses. is it possible? 
there is some 3dtv's without glasses needed out there ,
There are a few small screen size 3D displays that do not require glasses. The trade-off is that these products require that the user sit in a "sweet spot" generally centered right in front of the screen to get the 3D effect. More tech work is required to develop large screen size, no-glasses 3D that will also allow the viewer to sit at a reasonable viewing angle and move around while watching (which the active 3D glasses allow). Lots of development work is going on in this area. Here is one for instance: not long ago Apple received a patent for a rather complex 3D system that does not require glasses but instead tracks the position of the viewer's eyes so that left and right-eye information can be directed to the viewer regardless of where he/she sits in the viewing room.