I'm designing a selectlist that allows you to select multiple levels simultaneously. It works fine for up to 3 levels:
This is just an example, in some instances this model would accommodate product selection which can have pretty deep nesting, about 10 levels, in various categories. Beyond 3 levels, the idea of managing nesting with indentation and font sizes seems ludicrous as it could be infinitely deep.
Any thoughts or examples would be greatly appreciated.