This deal has ended.
Buy.com has this Cavalry 500gb USB 2.0 External Hard Drive for only $99.95 after a $40 mail-in rebate valid through 6/25. Plus, shipping is free and there is no sales tax (except CA, MA, MD, TN). $0.20 per gigabyte matches the best deal I've seen on external storage. Plus, new Buy.com customers can use this $5 off $50 coupon and new Google Checkout users can get a $10 off discount for signing up (you can't get both).