A simple application based structure can be viewed with a built-in GUI debug/inspector.
$ erl
> observer:start().
Then can explore application structure and process hierarchy. It is not as dynamic as this and is coarser grained. But can inspect process state, loading, scheduler utilization.
Observer is way more practical of course, but there's something very cool and futuristic about the 3D version. You expect Tony Stark to reach out and modify some of the processes or something. (You guys didn't know that Iron Man runs on Erlang?)
Hehe. When I was interning at a company and they had SGI systems back in the day. I accidentally stumbled on Fsn (http://en.wikipedia.org/wiki/Fsn) and realized it was the file browser they used in Jurassic Park and it was real and I could actually use it.
People compare Fsn to a lot of things (WinDirStat, etc.) but although they all attempt to do the same thing, none of them really do the visualization the same way (representing the filesystem as a recursively-weighted zoomable pie-chart.) The one program I know of that's at all similar is DaisyDisk (screenshot: http://i.imgur.com/5adRu0h.png). Seeing that representation makes me honestly wonder why OSes don't just build this sort of visualization right in as a folder "view" alongside tiles and lists.
https://github.com/krestenkrab/erlubi
And here's what it uses to do the graphs, which is pretty cool in its own right:
http://ubietylab.net/ubigraph/
Too bad it's not open source software, though.