This video, via Raul Pena of Modular Wild, is an unofficial demo of the Halls of Valhalla reverb cartridge for the Tiptop Audio Z-DSP Eurorack module. 

The Z-DSP is a Eurorack module that can load software digital audio processing applications, letting it transform into many different types of modules. See the Tiptop Audio site for details.

The Halls Of Valhalla Z-DSP cartridge is available for US $75. The Z-DSP is required to use the cartridge, and is priced at US $435.