At DrupalCon I found out about some file that is suggested to be removed that, if I recall correctly, will tell you the version of Drupal installed on a site. I can't seem to find that information now that I'm looking for it, and I'm afraid I might have dreamt it.
Any suggestions? Psychiatrist? "If you're dreaming of Drupal, you have some serious problems. Still... wanna take a look at our website?"
Joel Willers