OctaneRender 1.2 in action. Otoy has just made the previous milestone version of its GPU-based renderer, originally released last June, available to students for free.
In practice, the deal also extends to teachers, or indeed anyone else who works at a school or college, since all you need to do to download the software is to register an account with a suitable email address.
We can’t vouch for the rest of the world, but both .edu and .ac.uk addresses work fine.
The only limitation is that you’re restricted to OctaneRender 1.2 – but since it was released under a year ago, you won’t be too far out of date.