Nicholas Chapman has been hard at work with updating his free unbiased raytracer Indigo (now version 0.5 released June 18th, 2006)
Main new features are:
- Experimental support for bidirectional MLT and bidirectional path tracing
- Measured complex indices of refraction for more realistic rendering of metals
- Image based lighting using HDR environment maps
- White balance setting for virtual camera
- Improved colours
- RGB and blackbody emission spectra
- Reverse gamma correction for textures
There is also an Blender exporter for Indigo, though at the time of this writing it is for version 0.4. I'm unsure if an update to the exporter is necessary, but if you're an Indigo user, post a comment to tell us if it is!
Take a look at our last Indigo post for a more closer look at the program.