An example: http://doc.rust-lang.org/complement-cheatsheet.html

trying clicking any of the TOC items on top and you will see the nice rust 404 page...

There is a bug somewhere where the current page is not included in the TOC link?

The link looks like this

http://doc.rust-lang.org/%5C#containers
When it should be this:
http://doc.rust-lang.org/complement-cheatsheet.html#containers