Commonly sold for gunsmith work and commonly refered to as a "gunsmith's vise" as well.
The made them with tall "pattern-makers" jaws like Balane's, and a shorter jaw like in Ryan's Blog entry.
Definitely not for heavy use, but extremely handy for quickly positioning parts for work.
There is an adapter for putting into the base, and turning the vise on it's side (not sure of the vid showed that, didn't need to watch it; got three of them myself...), so it is even handier.

on mounting on a corner, of a bench. Another option is to mount it on a mounting plate, put a "grip bar" on the bottom, and the clamp that into a bench vise (machinist or wood workers) or even a B&D Work mate.
Tarnished, Love the Jacobson! Does cinching the vise lock it in place also?
