This is old technology, made new...
Basically taking ram and presenting it as a hard drive:
http://www.radeonramdisk.com/
So the idea is if you have extra ram, you can take that ram and make it a hard drive space; which is kinda what an SSD is; but its system memory not slower SSD memory for capacity.
I may try to play with this soon, see how this works out with today's games.