[seanwoodhouse]

Firefox's 3D View was definitely an inspiration. Note however that Reveal lets you focus in on a view within the view hierarchy, which is handy when you're only interested in one part of a large hierarchy.

Symbiote (https://github.com/TestingWithFrank/symbiote) and DCIntrospect (https://github.com/domesticcatsoftware/DCIntrospect) were also inspirations.