I have a very rare Cassowary eggshell for sale. It has one small hole in the end, has been drained and cleaned. There are probably less than 50 of these birds left in the US, and eggs are hard to come by.
I breed Cassowaries, yes they are very rare. Emu's are the most Docile of the Ratites by the way, they get very tame, and its extremely rare one will ever try to attack you, and even if they do, they only go as far as you let them...they are big whimps, and are all bark and no bite. Rheas are the second most docile, but the males can get extremely aggressive.
Cassowaries are neat looking birds, but the wild ones can kill people! Don't know about the 'domesticated' ones, as I've never seen one close up enough.