The world's most expensive stamp, the "British Guiana 1c Magenta," was sold for over $9.5 million in 2014. elaborate
Birdwatching is sometimes called "birding," a term considered more modern and less stuffy. elaborate
The first geocache, placed in 2000, was hidden by Dave Ulmer and was only intended to last a few weeks. elaborate
Amateur astronomers have discovered numerous comets and supernovae, contributing significantly to professional astronomical research. elaborate
Wildlife photographers often spend more time waiting for the perfect shot than actually taking pictures. elaborate
Ferry modeling often involves simulating complex hydrodynamic interactions, meaning the model needs to account not only for the ferry's movement through the water, but also the waves and currents it creates and interacts with. elaborate