Wordpress Chunky - A simple plugin for creating "chunks" that can be accessed VIA shortcodes
Simply add it to your plugins directory, and activate.
You'll get a new menu entry that lets you add chunks of code in the same style of posts/pages.
On any page (Including inside chunks!) you can call:
[chunky id="{id}"]
or
[chunky title="{title}"]
Where {id} would be the ID of the chunk, and {title} would be the provided title, and your code will be injected.