I recently did out my old 401B after the screen fell off my Galaxy Active2. It charged right up and still lasts about a week.

Finding a new band was a PITA because of the weird segmented hinge bit but one person was selling diver bands for it on Amazon (I think it was Amazon)… Really not bad for a watch from a decade ago.

Edit: Yes, you can still use them without the OG servers being up, look up ‘Rebble’ (rebble.io)