My main rig is running 2 x 128GB Crucial M4 SSDs in RAID0 and a 1TB WD Black. I know running SSDs in RAID0 is a bit overkill, but I was running out of space on my single M4, so why not RAID another for maximum e-peen?
I also have a NAS box frankensteined from my old machine, running a 2TB WD Green, 3TB WD Green, and 2 x 3TB WD Red. One drive is for parity so i have a total of 8TB usable.