Panasonic | 12.5mm f/12 Lumix 3D G Lens for Micro Four Thirds Mount Cameras – $49.99
The $249 lens is currently being sold with a $200 rebate offer, so your cost is $49.99. I just ordered one.
Officially, the little lens does not support video in 3D, but that is supposed to be easy to work around – just put tape over the electrical contacts on the 3D lens and use the feature in the camera (see menus) to use the camera without a lens. The effect of all this is to recorded side by side (left-right) video for the left-right eyes.
The lens is wide at 12.5mm (25mm full frame equivalent) and slow (f/12) but all that is fine for deep depth of field 3D. The main issue is that the lenses are very close together, which is only going to be useful for relatively close in subjects. However, since I currently used paired cameras with a roughly 3″ and 6″ interaxial distance, I figure the narrow interaxial on the 3D lens will be useful for very close in subjects. Looking forward to trying this for 3D video!