I was looking through the FBI law enforcement publication archive and found something about a concealed knife in the shape of a 30-06 cartridge. Has anyone seen one of these or know who manufactures them?
http://www.fbi.gov/publications/leb/2004/mar2004/march2004.htm#page_10
About a third of the way down.
http://www.fbi.gov/publications/leb/2004/mar2004/march2004.htm#page_10
About a third of the way down.