Okay, this thread has taken a turn to a subject that I can't resist jumping up on the stump for. I agree with the general guidelines for 'inappropriate items' in caches in urban areas or areas that are easily accessable to the very young cachers. But where the cache is going to be a 'drive n' hike' there is (in my opinion) no reason not to leave items such as multi purpose tools, knives or waterproof matches. These are TOOLS that I'd like to find in a cache, and anyone old enough to hike to a remote cache is probably old enough to learn how to use the tools properly.
I've been a Scout leader ever since my 16 year old son was a Tiger, and some of the first things we taught the Cubs were the proper use of knives and fire. At first the kids are very intrigued with the idea of being allowed to use these items, but through training and constant use, it becomes commonplace.
Training, not avoidance, is the key.