A lot... like Ankerson said. Actually I have never done a FULL inventory probably because I might not know where all of them are. I have knives stashed everywhere from the shed's, garage, car, hunting bads, BOB bags etc. It would take alot for me to find them all get them together and take a count. I have a good # of customs but most are productions, alot of SAK's and folders. I also have over 20 swords (not including machetes) and 20 + axes of different flavors.
I'd say my interest is when growing up I didnt have alot of money, my dad gave me my first pocket knife and I fell in love with using it. When I was able to afford my own I bought and learned and the process repeated. I love that a knife can be a tool, a weapon, art etc and it can be so simple or so complex. I use knives everyday for all sorts of things and I feel like I am always buying and selling to get new ones to find "the one" though I know there is never going to be "the one".