When I go to http://exercism.io/languages and see the list of exercises I can download, it would be helpful to have a badge next to them showing which ones I've already done. If I go away for a day or two or if I'm working through several languages it can be easy to lose my place and then I have to go into my filesystem and figure out where I left off.

Something as simple as "submitted" or a count of the iterations I've done would be sufficient.