Best Buy offers the Seagate Backup Plus 3TB USB 3.0 Desktop Hard Drive, model no. STCA3000101, for $99.99 with free shipping ($0.03/GB). (Amazon charges the same.) That's tied with last week's mention as the lowest total price we've seen for a 3TB USB 3.0 external hard drive since July. (It's a current price low by $45.) Sales tax is added where applicable.