A couple things I haven’t seen mentioned: - a keychain sized measuring tape I got as conference swag years ago - a geologists’ hand lens. I’m not a geologist

A couple things I haven’t seen mentioned: - a keychain sized measuring tape I got as conference swag years ago - a geologists’ hand lens. I’m not a geologist but it is useful on rare occasions when you need to see really small things. Though to be honest the phone camera magnification mode probably obsoletes it.