I guess most of you have seen the post about SSS skin shader ported from Arnold to Cycles by m9105826.
Now I don’t know if it was a port of the Shader code, or back engineered with Cycles shader nodes.
Anywho, PsyOp had a neat Shader for Arnold on their blog, that looks really good. Just giving it some notice here and if someone with them skills in Arnold and Cycles and time/interest to port it over exist here.
From my understanding we would at least need custom ray tagging to record a history of volumes the ray has been trough for this to work. But the shader is not only nested dielectrics and some other stuff like the dispersion is doable I think. Personally I am most interested in the nested dielectrics and the direct refraction. I don’t know what’s possible using OSL tough.