Bluescreen

Bluescreen is a simple screensaver file that can be used to play a prank on a fellow computer user as it displays the dreaded BSOD (blue screen of death) when the computer enters in idle mode.
The application is devised by SysInternals, a company that is a subsidiary of Microsoft. It is harmless for the computer because it simulates the BSOD, which occurs because of both software and hardware issues.
The BSOD screensaver has been crafted to reproduce some of the details of the machine it runs on. Thus, on Windows NT it pulls the build number and even the processor revision along with the loaded drives and disk properties.
In the case of Windows XP and Server 2003 it mimics the startup screens specific to system boot operation, which occur at a 15-second interval. On NT 4.0, the tool manages to imitate a disk verification (chkdsk) that ends serving up all sorts of errors.
A keen eye may be able to determine that this is actually a bogus screen, but only in some cases as the application slips messages that do not always make sense. Unlike a real scrensaver, Bluescreen does not react at mouse activity and the only key that brings up the real computer screen is Esc.
The screensaver can be installed by right-cliking on it and choosing the “install” option. This way the Bluescreen option appears in the list of available screensavers.