Scanning parks and beaches with one of these can be a unique and fascinating hobby.

If you're like most people, you have a hobby that keeps you busy whenever you have downtime. Whether that's collecting highly valuable retro video games or going hiking with your favorite tech gadgets ...

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more› By Tim Heffernan Tim Heffernan covers air and water filtration, as well as ...