The thing I find the most disappointing about mineral dowsing is that it doesn't work, actually. For a rockhound like me, I'd be the first to sign up for classes if it did! I've been rockhunting for some time and I've yet to find some natural New York State gemstones like flourite and sphalerite.
The depressing part here is that despite the fact that it was all well and truly debunked, this English fellow nonetheless finds work to this day as a mineral dowser despite being told his power just doesn't work. He seems like a nice older English "chappie." I strongly suspect he actually believes he has a power and isn't aware of the "ideomotor effect."
Another YouTube poster devotes himself to explaining the truth behind so-called "true" supernatural tales like the Bell Witch of Tennessee and the Philadelphia Experiment, stories that have long since been shown to be false but still remain in circulation for whatever reason. They're fun to watch.
This one is my personal favorite, the story of the Bell Witch:
In general, stories of this type don't do any harm (unlike, say, creationism, which is poisonous to scientific understanding). However, while fantasy and ghost stories are normal, healthy and lots of fun, it is vital to distinguish between the real world and fantasy and not confuse the two.