John Nelson of IDV Solutions put 56 years worth of tornadoes on a map. John plotted each tornado's path and used brightness for its F-scale (level of intensity). He also added secondary charts for deaths and injuries and frequency by F-scale.
It makes a gorgeous map. I would love to see the data incorporated into the wind map.
So... practically speaking, if you live in the Midwest or Southern US, you should probably put this on your reading list.