It can be handy sometimes to have an icon on the desktop that will lock your screen quickly if you have to rush off somewhere quickly.
Here's how to create such an icon,
1. Right Click on the Desktop.
2. Select New and then Shortcut from the Menu.
3. In the box provided enter the following
"rundll32.exe user32.dll, LockWorkStation"
4. Click on Next and give the Shortcut an appropriate name.
Now when you double click on the icon your screen will lock up waiting for you to enter your password.
Have Fun,
regards
Steve