Hi,
For the most part, Indiana Jones and Silent Ninja are correct - the vast majority of 3D Blu-Ray films require a 3D TV set and 3D Blu-Ray Player.
However, there are occaisional films that aren't released in true 3D, but in the old stereoscopic format, that requires you wear paper glasses with red/green or red/blue lenses.
These kinds of 3D films can be played back on any TV with any kind of Blu-Ray player. But they are few and far between.
PIRANHA 3D on Blu-ray is that exception, as it contains:
1) A 3D version that can only be played with a compatible 3D TV and 3D Blu-Ray Player, and
2) A 3D version that can be watched on any TV, using the enclosed card glasses, with red/blue lenses in them.
Pooch