Not a Raid no, you can get a cheap 64GB HD and use it as a drive cache on a normal HD, inside the Raid software its simple enough to setup.
The HD will act like a Hybrid HD, things you load a lot will speed up considerably though things you don't will come through at normal HD speeds same as any Hybrid Drive.
Its the cheapest way of gaining a speed increase on a normal HD.
64GB is the Max amount of any SDD it can use to do such.