Well, sort of. That's there more so if you don't have a torch
or a night-eye spell. (and to freak you out about the monsters)
My main easter eggs are the 5 of the "Arrows of Slaying"
from Bloodmoon that I hid in Apocrypha and scattered about.
Some are hidden in relatively easy to get to areas that you just
would never really look, and others are hidden in places that everything
about the place tells you that there shouldn't be anything there.
1 requires you to use the grab key (or else you'll die)
1 requires you to make a mess of the main hall
1 requires really great acrobatics (the skill) and agility (on your part, not the char's)
1 requires you to look behind Him
1 requires you to look below Him
EDIT:
Holy crap! While I was typing this I just a got a job offer!

Woo hoo!