I've done a lot of work on my own house and have ran into a lot of funky situations - including one case where neutral was connected to ground at a remote outlet. I can't forget the experience where I touched a conduit and 'felt' the electricity. Worse, I remember thinking "now that shouldn't happen" and grabbing it again to be sure.
Fortunately, the load was such that it wasn't anything major - just a low level pulsating sensation. On my house it was a particularly bad situation given that the house was built in ~1965 and the ground wire is very small (~AWG 20?). BTW, thanks for the other links - very informative.