Until you get out there, you never know what you might find. But you need a reason to get out there. So (if it’s good enough for pirates, it’s good enough for you) send yourself on a treasure hunt.
Making your own list – particularly if you can impose it on others – is part of the fun, but to get you started here are some suggestions for things to find: a person who looks like their pet, an equation, something that belongs underwater, a fictitious animal, foreign money, some food that could hurt you. You can document them with photographs, drawings, descriptions or whatever takes your fancy. For variations, set yourself a list of tasks as well (sing on stage with a band you’re not a part of, pretend you’re in an Olympic event while queuing at the supermarket…). Have your friends join in, compare results and give prizes.