A very artistic view of a collision inside a particle accelerator. 100.01% Blender and Cycles. The rounding error is due to the tiny bit of contrast I added at the end with the GiMP.
Full size here: http://goo.gl/t74jG (Just download it instead of fighting the stupid viewer.)
It’s not super high quality because it was for the previous week end challenge. The subsurf modifier can’t cope with the low poly nature of the mesh but it gives more details in every corner… And the grain makes the image just not too perfect. (It’s only 400 samples but, after 1h40, I wasn’t in the mood to check how long it would need to render at 800.) I kinda like it the way it is but, even if I won’t redo it, I’ll take any criticism for the next time.