We have problems with deer, raccoons and skunks. We have been successful using SSScat to keep the raccoons and skunks off the deck.

http://www.petsmart.com/product/index.jsp?productId=2751025

I am considering taping the SSScat to a bamboo pole (at deer eye level) near their favorite plants. Has anyone else tried this?

This stuff really works on cats -- see:

http://www.youtube.com/watch?v=iG0ciR_k8ck