I readily admit that I'm a huge tank nut.
The German Panther Tank (1943-1945):
Its classic profile is the epitome of what a tank should look like. It rendered work-horse service for the Krauts in WWII, and it's my personal opinion that had the Germans focused primarily on the production of Panthers, similar to the way the US focused most tank production on the Sherman, to the exclusion of the 50k designs they had including all of the behemoths(the Tiger, King Tiger, the planned Mouse, etc.) that were useless in urban areas then the war might have turned out much differently (though they still wouldn't have won).
It's a mother beautiful tank.