Here, I'll bite. My favorite new use for screen is 'launching' all the fiddly bits of Rails development. So it starts my server, starts one version of spork for rspec, one for cucumber and then starts up autotest (which notifies lib-notify...) anyway, I spent a few days tweaking, but it's mostly still cribbed from elsewhere. Thought people might find it interesting with all the command line options screen has.
I've included my (dead simple) .screenrc too.
All at: http://gist.github.com/499251

I totally agree with you, it took years for me to see what the deal was with screen, and now...