Looks more like spam to promote someone's $25 product. If you want to
lockup your computer while you are away, why do you care if the screen
is visible or not? Just define a shortcut or programmable key on a
keyboard to:
%windir%\system32\rundll32.exe user32.dll,LockWorkStation
See Microsoft's KB article 313884. From their web site, "monitor
incoming messages, while restricting access to your computer". So what?
To monitor means YOU are there at your computer. This author has a
problem with roving gangs of thugs kicking him out of his chair and
physically taking over his computer? If you're walking away from your
computer and want it locked up immediately as you leave then YOU won't
be seeing anything on the screen, anyway! If you want a display showing
some animated sale promo and don't want the public doing anything with
the system, well, just remove the keyboard and mouse.