Bill, thank you very much for responding. Your input is exactly what I needed. I found lots of choices under "remote power switch." What I'm deciding now is whether to hand over all the network maintenance duties to a full-featured remote switch like this
http://www.remotepowerswitch.com/remotepowerswitch.html
or continue to allow Indigo (and the above script) to monitor the modem and routers and just get a simpler, telephone-line based reboot switch for rebooting the computer:
http://www.remotepowerswitch.com/rps-home.html
For some reason, dalenis' script is causing frequent modem rebooting on my network (several times an hour) and I've disabled it... something is going on that is interfering with that ping... yet for all my internet needs, other than a hang once in awhile, I'm not otherwise aware of a problem.