Blender 2.42 note! You need Yafray 0.0.9, which is available now.

Yafray is an open source ray tracer, offering Global Illumination and Photon Mapping, for high quality photorealistic rendering. Since Blender release 2.32, export to Yafray is integrated in Blender (read more on the Yafray plug-in page).

Yafray is hosted and maintained independently from Blender at www.yafray.org.