Real-time dynamic GPU path tracing

A small teaser of something I'm working on, rendered in real-time on a GeForce GTS 450:

http://www.youtube.com/watch?v=1Q0z2E_mfXY

12 samples per pixel, max path length = 4, 584x266 render resolution, Stanford Bunny with 69k triangles (rendered in about 0.4 seconds on a low-end GTS450):

This will eventually become a full-fledged game inspired by this video:

http://www.youtube.com/watch?v=pmu5sRIizdw