Circuit City has the 120GB WD 7200rpm 8mb cache HDD for only $40 after two rebates. Unfortunately this is not a web offer (you can go to http://www.circuitcity.com, look up WD1200JBRTL, and check for availablitity at one of their stores though). Heh, I've been needing to get one of these for my xbox so its worth the drive for me;) Here's the rebates:
$50.00 Rebate
$30.00 Rebate