Why Gentoo?
I just came across another good post on why it's worthwhile to use Gentoo, if not permanently, at least temporarily. Kathy Sierra posted on the Passionate Users blog about the inverse relationship between efficiency of your tool and your understanding of what it does. The more autoconfiguration there is, the harder it is for you to figure out what to do when you've got a setup that doesn't autoconfigure.

A commenter on that post pointed to an earlier Joel Spolsky (Joel on Software) post on leaky abstractions—in other words, an incomplete, simplified metaphor that sometimes breaks down. When you don't understand both sides of the metaphor, you can't figure out why everything's busted.

In the same way, automated tools suck. They're great once you understand the black box they hide from you, but ignoring that black box entirely is a route to disaster. That's why you should try Gentoo, or LFS, or some similar DIY distro that gives you the opportunity to understand what all those fancy GUI tools really do. Someday, they'll break. Will you survive, or will you take your toys and go home?