If you install the console version as a service, instead of selecting automatic during the initial setup, select manual.
When you leave for the day, go to services ( you can put a shortcut on your desktop if you want ), and start it. It'll then run while you're logged off. When you come back, you stop it.
The GUI version won't run while no-one is logged on... so that isn't really what you want.
But I think, that as long as you don't setup the optional advanced features, it won't interfere with your databases at all. The client is very good, about releasing cpu resources, and won't interfere with all but a very few limited number of programs.
Thanks, Klutz...I'll be trying that right now.