This single little contribution of mine to the Revit community has been the most continuously requested thing I've done. Something so seemingly simple borne out of a fellow user's request.
I'm glad that this has been useful to so many. Now I've updated it for 2009 and added another tag as well as a "schedule as tag" approach to displaying the total length at the end of a path. You can now download it freely instead of having to email me to get it! Happy Exiting!
Egress Path for Revit 2009
Egress Path for Revit 2008
Previous related posts:
Egress Path Uh Oh!