Dr Lorenzo Picinali of Imperial College London has been in touch about a set of binaural software tools that ICL, in conjunction with the University of Malaga, have developed. The fruit of their labours was the 3D Tune-In Toolkit, and while it was initially created as a research tool, the people behind it considered it such a useful bit of programming that they're essentially giving it away for free!
The algorithm itself has been released as an open-source resource, and is available on GitHub, but non-programmer binaural enthusiasts can get in on the action too, thanks to a number of self-contained software tools that employ the same algorithm. For example, the Test Application programme is essentially a stand-alone spatialiser, into which you can load up mono WAV files and move them around a virtual space. Usefully, the Test Application speaks OSC (Open Sound Control), so using a phone, computer or tablet running one of the many freeware OSC apps around, you can perform real-time head tracking, and whizz your mono audio sources about in the virtual 3D space (see video below).
As well as performing immersive audio tricks, the Test Application also allows you to simulate the effects of hearing loss, or even of wearing a hearing aid: