Double-sided disk map projection – Gott, Goldberg, Vanderbei

Three scientists came up with a completely new map projection. And it's pretty good.

It retains proportions of areas, angles and distances.

One can see that most of the landmass is in the north hemisphere. Area of Arctic and Antarctica are proportionally correct.

Perhaps the disadvantage is that, if printed, you see one side or the other, not both at the same time. Bot the globe is also like that.