Thinking on a couple things
There are two ideas that have been buzzing around in my brain lately.
The first idea is a Perl CMS that is all Perl and that scales from CGI (because that is what a lot of cheaper hosting sites offer) to whatever you want to scale it up to. I don't mean scale in the traditional sense here, though I would want it to scale that way as well.
The second one is a server monitor along the lines of a Nagios but all in Perl with plugins written in Perl.
Neither of those is necessarily a "good" idea. They are just ideas. Throwing them up here to maybe tickle myself later with them.