A wonderful plugin to easily create many custom sidebars. These sidebars can then select in the creation of a post / page / custom post type / categor
Create small posts outside the main flow of your blog. Integrates into any theme that supports widgets.
Display arbitrary sidebar content conditional upon a particular post or page.
Adds a sidebar comment (an inline box that includes commentary text) to a post
This plugin allows you to change the DIV/Container element of each widget to one of the new HTML5 Semantic tags.
Change the post format on all posts in one category. Useful when you switch from styling "Asides" based on category to the new post formats.
The SBD Aside plugin is a WordPress plugin that allows bloggers to easily create small side-bars for there entries, called asides.