From: http://splutterfish.com/forums/showthread.php?t=21260
chipNuts:

Vray Mat to B2Adv Mat

Heya Fishies, I created a script that allows you to convert a vray material to a brail2Advanaced mat. There are some things that literally won't transfer between the 2, such as translucency settings in vray to b2, but for most used slots they transfer seamlessly. Two-Sided, Diffuse, Bump, Displace map, Env map, Reflection with basic glossiness settings (quality settings aren't the same, so haven't figured what to do with that one), IOR based on vray Refraction only, since vray has IOR for both reflect and refract. Refraction with basic glossiness settings. Be aware, vray has an actual Refraction AND opacity slot, this takes the vray refraction and drops it into the b2 opacity, since that's where b2 takes care of refraction a.k.a. opacity + IOR = refraction, so vray opacity slot is ignored, which it should be anyway, imo. Also, b2 opacity is switch to transparency to match the behavior of maps coming from vray. One last thing, the name of the b2 mat will be the same as the vray one it was created from. This has an added bonus of allowing you to just hit the 'Put to Scene' button in the matedit and it will update all instances of that named material. So simple! This is very basic, use at your own risk, blah blah. Future versions will go from b2 back to vray (just to be fair) , then on to animation and possibly converting more complex mats/fx, like car paint or sss, etc.

Thanks to Neil, (which created the original mat converter script this was inspired by), Richard (for script/brazil-specific help), Pixel_monkey (for the extra code I forgot), gk (for realizing the Os_Tx switch I needed) and anyone else I may have forgotten.

Weeee!

jackbird:

Updated it to work with multi/subobject materials.