Time Capsule alternatives

I have recently bought a MacBook Pro (my first Mac) and my wife is about to do likewise. I now want to purchase an external HDD for backups.

I like the idea of being able to backup wirelessly - the whole point of laptops is to get away from plugging things in. But the Apple Time Capsule, while neat, is very expensive, particularly the 2Tb version, which we'd require to have sufficient space to backup both computers.

My question is: is it possible to mimic the Time Capsule plugging in an HDD (formatted appropriately) into a router with USB ports?

Thank you for your help

Andrew

It is, yes. The Airport Extreme is probably the simplest route - but you can start with some of the suggestions and links in this thread (I used when I was researching the same) if you don't want to purchase the AE.