I have a huge backlog of cool URLs. Here are a bunch having to do with ray tracing:

• For SIGGRAPH presentations, see Stephen Hill’s page and my own. His is SIGGRAPH in general, mine is ray-tracing related only. Both have links to slidesets and videos, as released so far.
• There are hardcore commercial physical ray tracers out there, for real-world optics, material analysis, etc. I’d heard of FRED last year because of this cool research (friendly version here). At SIGGRAPH I heard about ASAP.
• Here’s a page of all publications related to Disney’s Hyperion renderer. Lots to chew on; today I read the short paper “The Challenges of Releasing the Moana Island Scene,” which brings up some tough questions (and their answers) for how to make a production model available to researchers.
• I found this presentation about path tracing Quake II worthwhile, in part because it discusses denoising in not-so-handwaving terms. Latest game version here, older source code here, watch the presentation here (sign-in required).
• This Unreal Engine tutorial on ray tracing has a lot of side-by-side comparisons. There’s also a video of pretty real-time architectural renderings using Unreal.
• Super-cray: a pinhole camera working through global illumination by using ray tracing in a Minecraft mod.
• And to finish on SIGGRAPH, here’s my album and Mauricio Vives’s album, which do have a few ray tracing related bits in them, including interesting predictions from a talk by Morgan McGuire. Let me know of more – there’s so much I missed.