I second this choice. I used pfSense in a multi-WAN corporate solution. I had fast & cheap cable for common users which failed over to a 3xT1, which was normally reserved for server traffic. Before the cable, we had DSL that was about the same speed as the T1 and toyed with round robin load balancing. Eventually, I convinced my brother to switch to this solution for his home network. He manually switched between 2 providers that both had 5 GB limits each month. This worked flawlessly until he upgraded to a better provider 2 years later.

Ooh! Beat me to it!

Ahh! The Google Sneakernet approach.

Wow. Just. Wow. Somebody knows their hard disk architecture.