Mine is because of the research and how it paid off...found an old postcard of an old amusement park. The amusement park is long gone and turned into housing for part of a college, but I noticed in the background of the old photo the rollercoaster ran along a set of woods that are still there. I went in the woods and found old remains of the cables that held up the coaster framework. There was a stone wall separating the new college area from the old woods and you could tell the woods had not changed at all (big boulders, old trees, etc.). I started detecting the woods and within a small area just 6 ft or so by 10ft. I found a 1908 Barber half dollar, several silver Washington quarters and several Merc. dimes. I surmise these either flew out of people's pockets while on the coaster or were dropped by workers or people going to the bathroom in the woods. Cool stuff!