Newegg has the 1.0 TB Samsung HD103SJ Spinpoint F3 7200 rpm hard-drive on sale for $55 -5 code "EMCKCKB22"
with free shipping this weekend.
This drive is fast (as mechanical hard-drives go) and it's quieter, cooler and cheaper than the WD Caviar Black
If you want to go faster, they have the 0.12 TB Corsair Force GT SSD for $255
. This uses the SandForce SF-2200 (SATA III) controller.