What always infuriated me when looking at Apple menus on OSX, when I was a user of it, was the icon for Option/Alt. http://km.support.apple.com/library/APPLE/APPLECARE_ALLGEOS/...
I can't remember if it appeared on old mac keyboards, but it definitely doesn't on modern ones and to me it just looks like a completely abstract symbol. I could never remember if it was control or option.