I agree with George Hill that if you can legally carry a gun that is your best option for defense. At home, I carry a handgun.
Unfortunately, there are still a number of states which make it very difficult to get a CCW. This is true in my home state of MD. Also many work places restrict the carrying of handguns. Doing so at my work will result in immediate termination.
It is for those reasons that I carry a defensive folding knife when outside my home. Legal, permitted at work, and effective when used properly.
My carry folder is a Crawford Kasper Fighting Folder. The REKAT Carnivore also looks to be an excellent knife although I have not handled one personally yet. I also prefer the forward grip so I did not consider the Hobbit or Fang.
P.S. I also agree with George that your knife will probably not be used on another person. I also feel that my handguns will most likely be used only to shoot paper targets and not another human. However, it still pays to be prepared.
[This message has been edited by Axel Yup (edited October 02, 1999).]