The second Exposé trick involves Exposé’s Application Windows mode (Control-F3 or F10 by default). In Snow Leopard, when you use Exposé’s Application Windows mode, Exposé will show you all windows from the selected application, regardless of which Space they may reside in. So if you’ve got Safari windows in three different Spaces, Exposé will present them all on one screen. If you then choose a window in something other than the current Space, Exposé will take you to that Space.

While this is logical, it’s also a change from 10.5—in 10.5, Exposé’s Application Windows mode would only show windows within the current space. If you’d prefer this behavior in Snow Leoaprd, too, open Terminal (in Applications -> Utilities), and enter this command:

defaults write com.apple.dock wvous-show-windows-in-other-spaces -bool FALSE

Press Return to execute the command, which won’t show any output. To make this change take effect, you need to restart the Dock. You can do this using Activity Monitor (find Dock in the process list, select it, then click Quit Process), or in Terminal (type killall Dock). After the Dock restarts (which it will do automatically), activate Application Windows mode in Exposé, and you’ll only see windows that reside in the current space.

If you decide you prefer the default Snow Leopard behavior, open Terminal again and enter this command (again, pressing Return to execute it):

defaults delete com.apple.dock wvous-show-windows-in-other-spaces

Restart the Dock again, and Exposé will once again show all windows in all Spaces in Application Windows mode. Thanks to Mac OS X Hints readers HitcoPhila and Mathew White for these two little Exposé tidbits.