Need a HDD, who doesn't..

Even after some online research I'm still clueless in this area. It doesn't have to be huge in capacity. <= 1TB is good enough. Must be fast (of course). What have you used? What would you like to use?

Some of my current specs:

Asus Crosshair IV Formula
AMD Phenom II x6 1100T
ATI 6970 2GB

Thanks!

Western Digital Caviar Black 64mb Sata3 model, or Samsung Spinpoint F3.

Depends what you would like to do? Most people would probably benefit from putting the OS and a few important programs onto an SSD, then have a large mechanical driver for any other storage. This would improve the performance of the system much more than using 2 mechanicals in RAID.

I have 2x2TB Seagates, 2x1.5TB WD Greens in raid 0, and 2x150GB Raptors in raid 0. I don't notice too much difference in speed between any of these hard disk setups.