Send an application to a specific Space

Solution 1:

I don't think there's a particular kayboard shortcut you can use, but if you click on the app's title bar and hold mouse button and then click ctrl+n where n is the number of the screen you want to send it to it will be moved there. Bear in mind you will be moved there too.

Solution 2:

If you want to always use the same Space for an application, then you can assign it from the "Esposé and Spaces" preference panel. "Every spaces" allows you to see the windows of that application in every spaces, independently from the space where you opened that application.

If you want to move an application window from a Space to another, then click on the Spaces icon shown in the dock, and Spaces will show you all the available spaces; from that screen you can move a window between spaces.