Vises are useful shop tools.  They come in more varieties than I realized, each designed for a special purpose.  True, they all hold an object in position, but objects come in all sorts of shapes materials, etc. 

Vises come in different sizes depending on the mass of the work they are designed to hold.  The holding surfaces are adapted for the characteristics of the work they hold.  For example, someone who is going to use the vise to hold lengths of black pipe while threads are cut is not terribly concerned about a few scratches.  The important thing is that the work be tightly held and not slip.  

Bench vises. Are designed to be mounted on a bench or worktable so they hold objects at a comfortable level.  If you click the bench vise link you will be taken to a page that shows you all the current Ebay listings for bench vises.

Fly tying vises. Fly tying is a popular hobby which requires holding a small fishhook in a position where it is easy to wrap it with thread, yarn, feathers, and other decorations.  If you click the fly tying link you will go to a page where you can see all the Ebay listings for fly tying vises.

Below are the results you see for an Ebay search for "Vise".  If you click on one of the links you will go directly to that auction on Ebay.