3d - scanner: not for scanning objects but for measuring distance and size. gas/geiger - o.k., ageiger counter is a bit over the top, but as they are cheap why not having something that warns you in case of danger on your wrist. you're not going to have that lifesaving equipment on you just in case, but the watch will probably be on your wrist.
and yes, a smartwatch that's not as thethered to your phone as most of them are right now is still a smartwatch - it's mostly an I/O to your mobile carry around computing device a.k.a. phone, sure. but that phone's cpu will probably dissolve into the cloud anyway, but the IO devices will stay. (besides, the same argument can be made about a smartphone that can't do much without a connection)