This is an awesome feature. Naturally, Emacs also supports this, right out of the box. Just use M-x htmlfontify-buffer.

Here's a sample of the output: http://inst.eecs.berkeley.edu/~tikhon/Interpreter.hs.html

EDIT: Also, note that while the VIM one uses a bunch of <font color="..."> tags, the Emacs one uses a bunch of span tags with reasonable class names like "function-name" or "string", so it produces much nicer code and is easy to use with your own CSS.