Ok well I offered this up in the evolution map thread. There seemed to be some interest in such a map. So as not to derail that thread we will move the question over here.
Would you be interested in a contest where you design a map and then plot migration routes for a species as it spreads out from its cradle into new parts of the globe? The most common versions of this type of map are the human migration routes with all the arrows moving out of Africa. However, someone else suggested using gradients to represent different times in history during the migration. I am sure there are also many other ways you could show how your group traveled outwards from their birthplace.
Edit: Bartmoss has a very good point so then not just any specific migration map but any map that shows the travel and wanderings of a group. It could be a new species, the colonists of an empire, etc etc.

