Testing CPAN.pm without altering its code
is a new idea. It involves testing a commandline interface that uses both STDOUT and STDERR. While this isn't necessarily new, doing it in such a way that tests can be modified/added without significant work is new.
Not to mention that the person who manages to do it in a nice fashion would get some serious props.
My criteria for good software:
- Does it work?
- Can someone else come in, make a change, and be reasonably certain no bugs were introduced?