East London Museum
There's definitely something fishy going on at the East London Museum. In addition to a whole section on the discovery of the coelacanth, the museum has a large display of preserved fish, including an enormous manta ray. For a different kind of fishy, check out what is claimed to be the world's only surviving dodo egg. Probably the most worthwhile exhibit, though, is the extensive beadwork collection; it's culturally interesting and just plain beautiful.