Version:            (using KDE KDE 3.5.1)
Installed from:    SuSE RPMs
OS:                Linux

The way things are now, if the user goes away from the computer, it either wouldn't start doing anything or would start a screensaver.
The "Screensaver" should be replaced with a metaphor I'd call "Idle". What's done while "Idle" is on would be the following (all of it optional):

-Kat would update its index
-Distributed computing applications would start working at full power
-The KDE session would be saved (ever got a powercut after opening 100 important windows?)
-Kopete/Konversation would set the status to "Away"
-Software would be updated (which shouldn't happen most of the time because it hogs down the connection and things like web browsing become very slow)
-A screensaver would be activated
-...perhaps other things

This should be activated either manually or after a specified amount of time idle. The manual activation should be done in a very easy way, so it'd feel natural for the user and would be easy to get used to. For example there could be a button immediately on the left of the "Toggle showing" button at the right (by default), saying "Leave". Reentering "busy" mode would probably be done by pressing any key.