I finally had the chance to test the new Logiitech Touch application (Logitech touch)
What a great little app. You essentially install the server side of this app on the computer you want to control, then run the app on your iphone. The iphone app lists all available (controllable) systems on your network. You then can use the mouse / keyboard by moving around on your touch or iphone.
This is a great feature to add to my Home theater system (windows media center). It seems to be nicer than typing on my windows remote.