Eggshells Fertilize the Garden?

I love my daily visits from the deer.  They have made themselves quite comfortable in my yard and surrounding woods and while I love to watch them, I have been worried about them devouring my garden.  I ask myself often, how can I make my flowers unappealing to them?

I stumbled across an article stating that eggshells, crushed and sprinkled in the garden and around the plants, may deter deer.  Another positive is that eggshells are composed of the same nutrients that are found in commercial fertilizers.  Eggshells are 93% calcium carbonate, 1% nitrogen and 0.5% phosphoric acid.  This makes them an excellent fertilizer. 

Too good to be true?  How can something I use every day be so helpful in the garden and save tons of money?  I plan to find out.  Check back often for updates on my eggshell fertilizer/deer deterrent experiment.