Lightscape

Lightscape bounce energy from surface to surface (radiosity) by subdividing the geometry to attain detail. The radiosity pass is very time consuming. Render time is 3-4 minutes per image.

Pros:
Really cool OpenGL preview, real-time exposure.
Quick rendering (after radiosity pass, only raytracing is required).
Exceptional for interiors (poor for exteriors).

Cons:
Radiosity quality depends heavily on your model (quad faces are prefered and overlapping or intersecting geometry must be avoided at all cost). - Tesselation errors are difficult to correct.
Only simple texture mapping is supported.
Good fresnel reflections, but no glossy (blurry) reflections.
Lightscape is single threaded - no render farms, dual core etc.