Don’t get me wrong, the crash has been and will always be a special watch, not just for Cartier, but as a unique creation of the 60s.
But there are plenty of other brands that have been unique shaped cases, like VC for example, some of them have significantly better watchmaking chops than Cartier, and are much rarer. There are so many unusual case shapes from the 30s and 40s that get nearly no attention.