Interesting BMW 6-series comparison...

[240Z]

BMW 6-series

Remove the bizzare trunk lid and you have...

The back of this. (minus the spoiler)

There are a few subtle differences, but I think the similarity is striking, especially in the taillight size/shape, exhaust placement, and overall tail shape.

 

[ND4SPD]

Holy crap, your right, its creepy how they almost look the same, but from the back view they look nothing like each other, good find though.

 

[pimp racer]

The lights on the porsche is a but bigger.