Have you already heard about Thinglink images?
Maybe not, because those can not (yet) be embedded into WordPress.com blogs (WordPress.com doesn’t support third-party plugins). I like this concept and see a potential for it here in WordPress also, so I have to use a workaround: post an image and link that to Thinglink service.
Here is an example. This is HDR image I took in Rome. Click the image, and you will find more information about the picture’s elements.