‘Doctype’ is one of those ‘where has this been?’ type of websites. The elevator-pitch description:
Doctype is a free question and answer site for web designers. You can ask questions about CSS, HTML, web design and email design.
Everything is editable, just like a wiki. This means answers are accurate, neat and up-to-date.
Awesome. (Via Daring Fireball.)
Update: Here’s a great example of a question with great answers. Again, where has this been all my life?