I have round buttons that I had made showing my crest. There are photos of these buttons floating around in previous threads.

I have seen many heraldic buttons. Some Stewarts of my ken have buttons shaped like oak leaves. I have seen pine cones, eagles, seals, wolves, castles, even bare-breasted ladies! Hugh Cameron of Kilwhillie, in Sir Compton Mackeanzie's wonderful books, has a double with buttons of jet, in the shape of some Cameron hound, with eyes of ruby!