My last car, before my Cayman, was a BMW Z4 and whenever I would pass another Z4 there would be an appreciative nod, or hand wave, etc...a sort of 'in the club acknowledgement'.

Has anyone noticed this whilst driving your Caymans of other Caymans? The front windows make it difficult to see nods, but has there been any consistent method you have noticed or you yourself do?

With Porsches, the "wave" is usually done with a headlight flash. That's usually easier to notice than a head nod or hand wave from inside the car.