[CentOS] Multiple program instances or multiple log ins?

This all comes out of figuring out how I might run Evolution like I run Eudora.

I see where Evolution places its data in a hidden directory: ~/.evolution

Now why it is felt necessary to put all of this stuff in hidden directories is beyond me.

So it would seem that Evolution is treating each useid as a personality for the logged in user.

Given the way Evolution organizes its data, I could create some more Linux users, and either:

Give my main user file permissions to them and somehow run copies of Evolution using those /home/user directories. Anyone know how to do that?

Or do I somehow have to have multiple simultaneous logins? And switch between them? I know there is a way to have 4 desktops....