So, I've been thinking about setting up a dedicated scratch disk for when I work in Photoshop, Premiere, and After Effects as well as when I'm recording video at I very high bit rate.
What I'm thinking is two (older) 80GB Velociraptor's in RAID-0 as the title says. The random reads and writes should be pretty good based on what I found. I considered using an SSD but since I'd be filling it and emptying it often I'm pretty sure that a mechanical drive would be the way to go.
I don't need to much space just a nice speed boost over a standard 7200RPM drive.
Also, I have the option to buy the pair for $40.
EDIT: Here's the model number of the drives (WD800HLFS)