There are a number of wallet explorers that tag which Bitcoin addresses belong to semi-major sites/exchanges/ect, I don't see why someone couldn't do a similar analysis for CLAMs or at least for their CLAM addresses. I wouldn't think it would be difficult to find the majority of their CLAM addresses with blockchain analysis.
That's a good idea. Any idea whether any of them are open source or open to adding new coins?
None of the CLAM block explorers that I am aware of do the address clustering / labelling thing.