Drop anything into the Sidebar: images, uploads, Calendars, Widgets, Documents, Blogs, Podcast channels...

Put a Layout here, and it becomes a list of links to whatever is inside it. Uploaded files becomes downloadables with large icons, and Web Pages [like this one] are displayed in their entirety.

The Sidebar is also a good place for Widgets. You could put a Twitter Feed here, for example - or a Weather Report. Click the Widgets Picker in the Sidebar File Manager for a list of available Widgets.

Note that Widgets will only display when the Sidebar actually is a Sidebar. If you use the Sidebar as a Page Footer, it will only display Documents and Layouts. If so, just drag your Widgets into the SiteFooter Container instead.