This deal has ended.
Buy.com has the 1TB Cavalry External Hard Drive (model CAUM3701T0) on sale for $189.98, despite being $200 or more almost everywhere else. Plus, delivery is free and there is no sales tax (except CA, MA, MD, TN). 1TB (terabyte) is the equivalent of 1000GB, which is about 5 to 10 times the storage most standard computers have. And, this features one-touch backup.