Disable the mouse while you are away, with Mouse Lock
Mouse Lock is a portable program that dims your desktop while blocking your mouse cursor to the centre of the screen! The password window acts as a mouse trap, yet the keyboard will still work.
Since any application that opens through the keyboard goes to the background, it is practically useless.
Sensitive information may still be visible, if you decide not to make the screen completely black.
Mouse Lock would be perfect if it included a keyboard lock option, however, even as it is, it remains a useful program for what it claims to offer, making the PC impossible to use, without logging off, for those who don’t know the password.