One of the hardest things to do in WordPress posts, is to quote actual code easily. It seems WordPress is a bit too aggressive with auto-fixing your html and it always ends up being a hassle to post some simple code bits. This is perhaps why BBCode in forums is so popular, as it makes this much easier.
While looking up plugins for something else I ran across: CodeHighlight, which makes the process easier. With this plugin installed you simple wrap your code text with simple BBCode style brackets.
Example:
<a href="http://www.somelink.com">Some Link</a>You can download the latest plugin from here.