Considerate Not Found Page

A 404 page is an opportunity for a web designer. You have a user looking for specific content, and they haven't managed to find it.

Too many sites have a cute picture, or a pun, but don't help the user find what they want.

Have they misspelled a link? If you have a URL /color and the user accidentally tries /colour or /color), then you can help them!

It's a great opportunity to leverage search too. You have some search terms -- the intended URL -- are there any pages that contain that text?