Perlmonks is possibly the best thing on the internet.
Perlmonks has smart people who really know their stuff and can answer just about any question.
I'm often disappointed that I've never found forums (fori?) of similar quality for other topics, EG Apache, Linux etc.. I'm sick of all those linux forums where 1000 people can tell you how to configure your 3D driver but no one can help you figure out how the file cache really works. (Because they're all gamers and none of them is a sysadmin.)
Are there other forums out there covering other topics that are as good as (or at least in the same league as) Perlmonks?
I know there are mailing lists, but I hate mailing lists. (I just started ranting about why, and then decided to spare you. If you actually want to know why, let me know).