I have mentioned self-anointing (or self-lathering, as it is sometime called,
in at least the U.K.) repeatedly throughout the FAQ, so now it is time to
explore the hedgehog's one truly unique trait.  Nathan Tenny provided a good
description of this interesting and perplexing hedgehog habit:

    If you smell *really* interesting, your hedgehog will lick
    or nibble on you, back off, and suddenly contort itself, start 
    foaming at the mouth, and lick the foam onto its spines.  This 
    ``self-anointing'' has to be seen to be believed, but it's perfectly 
    normal.  It's not known for sure why they do it, but it probably 
    has something to do with self-defence; hedgehogs are *highly* 
    resistant to most toxins, and when they encounter something that 
    might be toxic, they get it in their mouths, foam, and cover 
    themselves with the toxic mixture.  The result is a toxic hedgehog, 
    which is really something to reckon with.  (Incidentally, the toxin 
    resistance of hedgehogs is truly prodigious and has been the subject
    of some research; they are one of the few animals that can safely eat
    giant toads (_Bufo marinus_), for instance.)

    One more last note:  We don't know why this happens, but even without 
    the benefit of self-anointing, their spines seem to have a mild 
    toxic/irritant effect; when you prick yourself on one, even slightly, 
    it hurts more than it should, and for a little bit longer.  No big deal, 
    just sort of strange.

One of the most effective ways to provoke a session of self-anointing is to
pick up your hedgehog when you have sweaty hands, or after having used hand
lotion, or a different type of soap.

In any case, once you have witnessed this entertaining act, and you have
calmed down enough to understand your little friend doesn't have rabies after
all, you will likely be convinced that hedgehogs do not have backbones.  It's
really hard to believe something as round as a hedgehog can twist itself into
that contorted a position.  It's also a bit disconcerting to learn just how
long that tongue is!