Or, I don't know, a second box on a second ISP line. That's what I do, but then again I live in a place where an internet connection with a static public IP address and several megabytes bw both ways is like 15$/mo (unlimited, of course).
Keep in mind that for residential cable or DSL service, a given neighbourhood is very likely within a single circuit, and is subject to congestion from nearby connections (subject to their own caps). So a second line might not be quite so useful as all that, though it's almost certainly worth looking into.
Multi-homing onto fully independent networks could be quite useful.
