Best value I've seen if you want to backup your PC and keep the data in your own hands. Costco is selling the 4 Terabyte Seagate backup drive for $160 starting next week (695080). You have to be a member, and can only buy five of them. Sale starts next Thursday, 1/31.

You can maybe get cheaper backup if you want to do it over the internet and have someone else store your data for you, but this is a very good deal for keeping your backups in your own hands. It's relatively slow because it's an external drive and is limited by the fastest plug you have on your PC (probably the USB connector unless your computer is very new). But who cares, you aren't going to be sitting there watching the backup .

Store the drive in another room, or preferably, another location if you want protection from physical disasters as well as drive failures.

By the way, that's 4,000 Gigabytes; how big is your hard drive?