After a few incidents of going over my Sprint PCS minute usage without any warning, I hacked together a Perl script that will log in to the sprintpcs.com website and check my minute usage for me. It e-mails me a warning if I go over a certain usage percentage. I thought I'd post it in case anyone else might find it useful: sprint-minutes.pl (link removed March 4, 2017, no longer works). I believe Sprint charges something like $3/month for a similar service. Note that you need a few extra modules installed, and you need the components for WWW::Mechanize that allow SSL connections. Consult your local Perl expert for help with this if you need it; I can't provide support here. It may well require tweaking depending on how standard your calling plan is, or other variations that I don't know about. And of course it's subject to breakage when Sprint updates the HTML code on their site.
Any comments or refinements are welcome. Enjoy!