Some from North America (sorry if these have been posted, didn't read the whole thread):
2011 Bud Shootout practice, lights go out
http://youtu.be/2I5jS1y85lo
Caused a delay before the race - Pace car stolen, 1986 Talladega
http://youtu.be/ICi3kIzSIZg
Andrettis - Mario hit a safety vehicle, Michael hits the car the safety vehicle was trying to rescue, Detroit 1991
http://youtu.be/KwEqjuvAZzE
And from this year's Daytona 500 - Juan Pablo Montoya's car breaks, spins, and hits the jet dryer causing a big fire!
http://youtu.be/uFm6o-qB6T4