I came to suggest geocaching! I've recently gotten into it and it's very cool and very gratifying! The geocaches are everywhere so if you plan well, you can find a few in a day. Some geocaches have been in places I go all the time, and realizing that there has been a little hidden treasure there all along is crazy. Some of them are in places that I've seen, but in areas I never would have otherwise explored. Even if you just try it out for a day, I'd say it's definitely worth giving a shot!