Here's a prototype I've created to show how the Mac desktop might be augmented with contextual information/images. I've been thinking about this for a while, but was inspired by the release of the Windows application, Fences. I'm using the desktop as a simple demo space, but in reality this information could be added to any spatial file/folder view. I look forward to your comments and ideas.
UPDATE: Rémy has pointed out the Mac app-in-development, Grape (thanks!). The developer has stated it's development is currently 'on hold', but it's stated plans are quite ambitious and would be something like a 2D combo of Fences and Bumptop.