Ke=1/2 M V^2 Not relativistic. So wildly low. But certainly a low bound. My point being that nuclear bomb grade energy is certainly in the ballpark.
By my back-of-the -envelope math it is 4,500,000,000 joules. The Hiroshima bomb is listed at approximately 10,000,000,000,000 joules. I bet xkcd is far more accurate, though.
It sounds like you might like “The Tao of Pooh”.
With that username and that quote, I expect that you are (like me) in your 60s.
Gold coins. I bought at the all-time high.