When I use Apple Remote Desktop (ARD) to reach another Mac, I like to leave the computer with an active screen saver after I access it.
Using Automator, I chose Automator from the Library column, and dragged Pause from the Action column into the work area. I set the pause time to five seconds, to give myself a bit of time to quit ARD. Next, I chose Finder from the Library column, and dragged the Launch Application action to the work area. Using the to pop-up menu in the Launch Application action, I chose Other (all the way at the bottom), and then navigated to /System -> Library -> Frameworks -> ScreenSaver.framework -> Versions -> A -> Resources. Once there, I chose ScreenSaverEngine.app as the application to launch.
I then saved the workflow as an application (File: Save As, and set the File Format pop-up to Application), and put it into Dock on the remote computer. Now when I'm finished working, I can click the icon in the Dock and quit the window in ARD, and I leave the machine with an active screensaver.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20050909150246155