Here's a fun thing I just learned from the Encyclopedia of Country Living:
"Margie Minard of Mt. Vernon, OH, told me eggs help those who have problems with
deer in their gardens. Her husband read that one of the huge lumber companies found out that deer hate eggs and had developed an eggy spray for their seedlings. She said 'We've just been throwing our used eggshells out here and there in the garden and among the berry bushes and the deer don't come near any more!"
Edit: clever forum software linked my mention of deer to "keeping deer out of your stuff"
thread which I will update with this info.