If you work in a multiuser computing environment, and you have full (administrator level) access to your computer, you might want to restrict unauthorized access to your "sensitive" files under Windows 95/98.
One way is to disable the Cancel button in the Logon dialog box.
Just run Regedit and go to:

HKEY_LOCAL_MACHINE/Network/Logon

Create the "Logon" subkey if it is not present on your machine: highlight the Network key -> right-click in the left hand Regedit pane -> select New -> Key -> name it "Logon" (no quotes) -> press Enter. Then add/modify a DWORD value and call it "MustBeValidated" (don't type the quotes). Double-click it, check the Decimal box and type 1 for value.
Now click the Start button -> Shut Down (Log off UserName) -> Log on as a different user, and you'll notice that the Logon Cancel button has been disabled.