Thought I'd clarify my thinking on the two prizes. The non-JK owner could win the JK knife, and the current JK knife owner could win maybe $20-$50 off their next knife purchase, or win a small production knife (like a traditional folder for example, could be a used knife). It was just a thought to possibly gain more participation. I know times are tough for a lot of people so kudos to you Taht's for offering up a contest and prizes.
Sponsoring some one else sounds like a good idea, but not sure how effective that would be in generating orders. I know I've gifted 3 JK's and that only resulted in one knife purchased. Most of the people I work with, and know that spend time in the outdoors aren't into sharp steel all that much. I can't see any of them spending more than $80-$100 on a knife, and that's probably pushing it.
One last idea, maybe have people pick one of John's models to fit in certain categories. Example, which would you chose for a necker, EDC, camp, kitchen, hunting, hawk etc. That would get people looking and thinking of all of Johns models. Could include what changes if any would they make to the design, what handle materials, what would they choose to make it their own custom knife.
The trivia contest sounds interesting. If you had to search the forums or John's web site for the answers, that could generate some interest in the different knives. Could be time consuming and would need to be creative to come up with the questions.
I think photos would be a nice addition to any contest you chose. Looking forward to seeing what you decide on.