Here is one idea... Write some perl code that will examine CPAN to determine how many times a particular module is used by other CPAN modules and scripts.
Sort of a googlish approach to module usefulness or popularity, I suppose, but I think the results would be interesting.
It would be more effective to know how many times those modules are used outside of CPAN, but obviously that becomes problematic. Perhaps something that could search the archive of comp.lang.perl.misc to see how many times a particular module gets mentioned?
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