Vegas, learned about unsprung weight in an interesting way.
I used to live in Maui and sailboard alot. I was learning fast and going out in bigger wind and surf every day. One day I was sailing not far offshore and thrown all over the place -- just couldn't control the board, it was tailwalking all over the ocean.
When I came in exhausted, a local wandered over and said "Yo, bra, big wind, small board". I changed down and it became immediately apparent what he was talking about. The mass of my [large] board was being accelerated by the [large] waves and overwhelming the suspension [my legs], throwing me around like flotsam. Kinda like riding a 600 lb dirt bike.
It is, no doubt, a universal law of going- fast-on-the-planet-while-burdened-by-gravity.