I'm creating a helper class for simplifying the creation of an option page in admin that could conceivably be used in a theme, a plugin, or a mu-plugin. I'm trying to make the class as easy to instantiate as possible, so I plan on determining programmatically which of those three places the class is being instantiated from.
I haven't come across any other ways an option page might be desirable, but I don't want to leave out a scenario that I just haven't encountered or thought of.