Mac OS X lets you invoke tasks like enabling your screen saver, or clearing all windows from your Desktop, by assigning specific actions to the corners of your display. Move your mouse pointer to the appropriate corner, and the assigned action kicks in.
You can use the Desktop & Screen Saver and the Dashboard & Exposé Preference Panes to assign tasks to the corners of your display. Both offer pop-up menus for each corner where you can choose any of Exposéis three modes, Dashboard, Enable Screen Saver, or Disable Screen Saver.
The problem I found is that the target zone your mouse pointer needs to be in isnit always very accurate, meaning that if your pointer is often near a corner, but not completely in it, the Hot Corner action may activate when you donit want it. For example, my lower left corner is set to activate the Screen Saver and sometimes it kicks in when my mouse is only close to the corner.
Use modifier keys to keep Hot Corners from activating unexpectedly.
To work around this little annoyance, add modifier keys to your Hot Corner actions. You can use use the Command, Option, Control, or Shift keys alone or in any combination. Just hold down the modifier keys you want as you select an action from the Hot Corner pop-up menus. I chose Command-Shift, which means that my Hot Corners are active only when I hold down those modifier keys and move my mouse pointer to the appropriate corner. If I donit hold down the modifier keys, nothing happens when my mouse is in a hot corner, which means my Screen Saver kicks in only when I really want it to.<!--#include virtual="/includes/newsite/series/quicktip.shtml"-->