This plugin turns code blocks -- specifically, <pre><code> blocks -- into much prettier-looking ordered lists.
wp-content/plugins/
.code.css
file included with this plugin contains some example rules for styling your code lists.Get it here.
Because <pre> blocks break the page. Long lines break the design, because they don't wrap when they reach the edge of a block. You can get around it by setting the overflow property, but that adds ugly scroll-bars all over the place.
An ordered list shows line numbers, so it's easy to say, "I did something cool on line 6". An ordered list also wraps properly and doesn't widen your pages. And hey, it looks good.