We shipped an update tonight that replaces the old cargo-culted Prettify syntax highlighter we've been using for years with highlight.js from Ivan Sagalaev -- you can support his open source through Gittip.

Highlight.js has numerous themes to choose from (we're using Tomorrow Night) and is a cinch to integrate. It automatically: finds blocks of code, detects the language, and highlights it.

Here are a few samples.

Ruby:

# Output "I LOVE RUBY"
say = "I love Ruby"
puts say.upcase

JavaScript:

function helloWorld () {
  // Log out to console
  console.log("Hello world!");  
}

helloWorld();

CSS:

.for-1 {
  width: 61px;
}

.for-2 {
  width: 62px;
}

.for-3 {
  width: 63px;
}

.for-4 {
  width: 64px;
}

No highlight:

$ gem install rails
$ rails new app
$ cd app
$ subl .

I'm still holding out for Sass/SCSS support -- there's this issue.

Check out the source on GitHub, the demo, or the developer docs if you want to add support for your favorite languages.