Displaying specified regions

[Jennifer Petrie]

Does anyone have any ideas on how to display a specified region of the
server's display on the client's screen.  That is, rather than the client
seeing the entire screen, I want the client to see only some specified
window or icon.  Ideally, I need to have this specified region be defined by
the user on the client machine by clipping a smaller region from the entire
screen display.

Any suggestions is greatly appreciated.  Does anyone know if realVNC is the
way to go or what about TightVNC?

 -Jennifer