Wanna tell your friends about the do's and dont's in your computer when they login in your absence. Well you can do it pretty easily by displaying a legal notice at system start up.
REGEDIT
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system]
"legalnoticecaption"="enter your notice caption"
"legalnoticetext"="enter your legal notice text"
How to Enable Quick Reboot
This Hack will allows you to use quick reboot function to restart Windows immediately without shutting down. When its enabled, you can restart the Windows by press Shift + Ctrl + Alt + Delete.
Navigate to:
HLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
Create a new or modify the existing String value called "EnableQuickReboot" and set it to "1" to enable it.
Note: USE this METHOD only when the system has stopped responding.