Dropshelf gives you a handy place to put files, images, text and web links. Just drag an item to the edge of the screen, and Dropshelf slides out.
Use Dropshelf to hold your items while you drag them between different windows, tabs, full screen apps and spaces.
You can also store things in Dropshelf to keep for later. You can have multiple shelves, and they will minimize out of view when not in use.
It supports copy and paste too, so you can save your clipboard contents to Dropshelf. It is also integrated with OS X in other thoughtful, workflow-enhancing ways — check out the User Guide for some tricks and tips.