I'd be very interested in one of the OP's questions:
in reply to Help me fill a gap in my server-side knowledge?
How do you start and stop them?
As in, once I start, for example, Dancer, running on my Apache server, does it intercept all http requests? If I have www.siteone.com already running on simple html, and I build www.sitetwo.com running on the same server (separate accounts), is Dancer going to try to interpret http requests to siteone.com? And if so, once Is tart it, if I realize it's making a mess, how do I stop it?
Time flies like an arrow. Fruit flies like a banana.