If your stuff is command-line based, why not just use backticks to capture the output of some shell commands in your test scripts? Simply generate some acceptable output and compare it to the dynamic output generated by your test script. I've misused the Test::* modules to test non-code things (such as DNS MX configurations) and it's usually very effective.
Can you be more specific on exactly what you're trying to do, how you want to do things and what you've tried? I think this is a great idea, it's just difficult to give advice without more specifics.