Idea from https://commons.wikimedia.org/w/index.php?title=User_talk:Matma_Rex&oldid=182354447#Upload_wizard_2:

Alert: the best part of the Wizard uploader is that you can let it go and do something else. It would be useful to have an alert when the upoload is finished and you are supposed to do something to go on, like a sound, a change of the color of the screen, or a java pop-up.

I'm not sure about sounds, and any popups we do won't appear until the user switches back to our tab/window, but we could try doing things with the tab title or icon. Inspiration: http://stackoverflow.com/questions/37122/make-browser-window-blink-in-task-bar, http://stackoverflow.com/questions/260857/changing-website-favicon-dynamically.