coloring inside the lines
Fusion offers a direct plug-in PCIe card solution.
Violin offers a direct plug-in PCIe solution. (Check their site, Each array can be direct attached to a single or multiple servers).
In Nate's example - You could have a DL580 with 4 10TB cards (not sure if you could add more due to power).
you can add 10 Violin Arrays to a DL580 G7. ( 10 5TB Arrays or 10 10TB Arrays or 10 20TB arrays or 10 16TB arrays or 10 32TB arrays)
And each Violin array is fully hot serviceable - I was at Collaborate a few years back when one of the Violin Guys demoed this to some people from TMS....
As for in-memory databases (rumors aside), Oracle has been performing all of it's work in-memory for years. Just ask Mike Ault, he will confirm that storage, flash or otherwise is for only for DB persistence..