I kid you not.
Rez has uploaded a mod which enables non-default skin colours, you can find it here
CmarNYC has also uploaded his rather aptly named ‘Skininator’ (it’s still in the moderation queue). I’ve been playing around with it, it’s pure gold. You can find it in the thread I linked to.
missy harries has also made a cool tutorial
Sorry this is so short, I’m buggered.