Is there a way to see whether someone else has started editing a post?  There are times that I'd like to fix a post, but don't want to duplicate someone else's effort or overwrite any edits they made, or whatever happens on a conflict.

Tom O'Connor recently asked about http://meta.serverfault.com/questions/3251/some-kind-of-edit-locking.  To be clear, I'm not asking for locking, just an indication that someone started editing the post already.