Sometimes, it’s nice to change the current windowmanager workspace on command line, for example if you desire to start a application exactly HERE or THERE.
For KDE you may want to do it with “kstart”. But a tool like kstart might not be available for your windowmanager, so have a look at “wmctrl” as well: http://www.sweb.cz/tripie/utils/wmctrl/.
Have fun
Usn