wow, I remember seeing a pic of that in maximumpc in like 03/04...They were insanely expensive(of course-back then) I don't know where you might find one.
From what I understand its like the i-RAM but with better bandwidth, however it only held 8GB of RAM, not very useful, at least to me.
If you are looking at something like this, might I point you over to the data storage forums for the new Fusion-IO drive, far more space (said to be bootable) and pretty cheap for what it is.