Thanks to all those people who recommended Workspace managers for
Windows 3.1.  I found 3 shareware Workspace Managers, from Australia's
MS-WINDOWS archive (monu6.cc.monash.edu.au), which mirrors some
sites in the U.S.  The three I found were:

1. WORKSPACES 1.10 (wspace.zip)
                                This was the smallest and simplest
   of the workspace managers that I found.  It is very easy to use.
   It displays a small window, containing 6 buttons, plus an extra
   button for configuration purposes.  One annoying feature was the
   title window that is first presented when it is run - you must press
   a key (not a mouse button!) for the thing to go away.  Also, it would
   have been nice if there was an "ALWAYS ON TOP" setting for the little
   window containing the workspace buttons.  Maybe some user-specified
   strings on the buttons instead of the numbers one to six might be
   a nice feature.  The simplicity and ease of use of this workspace
   manager makes it an attractive package.

2. WORKSHIFT 1.6 (wrksft16.zip)
                               While this workspace manager offered a
   few features that WORKSPACES 1.10 lacked, it was quite time consuming
   to set things up.  With WORKSPACES 1.10, all but the first workspace
   is initially empty.  With WORKSHIFT 1.6, you need to take "snapshots"
   of how you want each of your workspaces to look like - i.e. what 
   applications they contain.  Also, the main window is quite large,
   but this does allow you to have a small view of what is in each workspace.
   With WORKSPACES 1.10, there was no facility for viewing what was in
   a workspace without switching to it.  WORKSHIFT 1.6 provides this
   viewing functionality which is quite useful.

3. BIGDESK 2.30 and BACKMENU (backdesk.zip)
                            This is an interesting package, which contains
   a few other goodies as well as a workspace manager.  Other goodies
   include "Backmenu", which provides a pop-up root menu when you
   press a certain mouse button - just like in X-Windows.  The menu
   is totally configurable, offering unlimited depth of cascading menus,
   which is provides quite handy access to applications.  You could
   say it is a menu-based alternative to the program manager.  Also
   bundled in "backdesk.zip" is a program called "WRUN", which allows
   you to run windows applications from a DOS shell under WINDOWS
   instead of using the File Manager to run applications.  
   The actual workspace manager is called BIGDESK 2.30.  BIGDESK works quite
   differently to the other two workspace managers in that it
   doesn't provide a certain number of disjoint and separate workspaces.
   In fact, it basically enlarges your desktop by a configurable amount,
   and you choose which region of the desktop you want your screen to
   focus in on.  This means you can have windows overlapping between different
   viewing regions, unlike the first two workspace managers in which
   each workspace was isolated from the other one.  The BIGDESK control window
   allows to to move windows around your enlarged desktop.  Basically
   the control window provides a small scale view of your viewing area
   while your actual computer screen provides a large scale or blow-up
   of a particular section.