Note to self #1
Running Ubuntu, never switch from a virtual desktop to another while watching a .mov movie using vlc.
One could have naively believe that Linux could avoid the Blue Screens of Death.
Well, switching from a desktop to another, a violent crash occured. A multi-colored screen - obviously painted by a daltonian psycho-maniac - er... now I'll have to abruptely reboot my PC (power Off / On).
[sigh]