I was thinking of getting an SSG-5 for a personal firewall, but haven't had much luck finding one for under $700. There's
the Cisco ASA5505 for $520. It sucks to have user limits on it when the Juniper doesn't, but in the 50-user version, it has equivalent features for less.
I can directly power my 7960 from one of the two inline-powered ethernet ports, too!
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Update: I'm going to use IPCop for now. It's too cheap to not experiment with, and I can always buy a firewall appliance if it's not working out for me.