Move windows between KDE activties

KDE 4.6 Plasma Workspaces added support for managing windows in Activities, which are a sort of combination between virtual desktops and session management. But I still haven't figured out some basic functionality, and khelpcenter doesn't seem to document the new Activities feature.

Particularly, how do you move a window to another KDE activity (i.e. using a keyboard shortcut)?

If you click on the window top-left icon you will open the window menu; from there, if you have more than one activity opened, you will see a submenu entry that will let you select in which activities you want to see the current application window. Please note that any window can be shown in multiple activities at the same time, so, if you want to move it, i.e., from the "activity 1" to "activity 2", you have to check, in the said submenu, "activity 2" and uncheck "activity 1".

As far as I know, there aren't keyboard shortcuts, which is a true pity.

you can access the " operational menu " of the window ( the menu that unfolds when you click the icon in the upper left icon ) pressing alt+f3. then navigate the menu with arrows.