Scroll through some of these photos that rolled through Oklahoma Monday May 10, 2010. There were at least 26 [update1: estimates of 35] tornados that blew through over just a 4 hour period. Massive amounts of widespread destruction. One was a mile-wide.
This link will only be valid for a few days as this is a general dump for user-submitted photos. Make sure you see the 5 inch hail stone.
Here is a dramatic video of a small tornado blowing through Norman, OK. Notice the cars being blown around on the highway.
[Update 2] Here are some more pics from this storm system that rolled through. I like the hailstone in pic 26.