#2: Sep 6th 2016 at 5:44:52 PM
It's simply something to help designate two different characters that happen to share the same name. There's multiple Spider-Man, but they're not all the same person. One's Ben Riley, another is Peter Parker. Etc. This way you can tell which is which. It's a roleplaying tactic that helps, but is only really used in Script format or sometimes on a work page.
Shadow?
Kimera128
Since: Jan, 2016
Korodzik
Since: Jan, 2001
Total posts: 5

I see this all over the place on TV Tropes now. For instance, Clone!Jason or Peter Parker!Spider Man. Often the first part is spoilered (for good reason).
Unfortunately doing a search for "!" is pretty much impossible, either here or on Google. I only half-understand what that means. Is there a page referencing it?