Kittye: Markets are kind of like a seasaw, and as one one bit goes up, another bit goes down. As bond yields go up, that tends to be bad news for hightek high growth stocksn so they've suffered some really bad days recently. Kitty martin is the f t market's editor. He tells you about a guy named beeple who created a file composite of digital sketches taken each day for more than 13 years. Beeple sold his non fungible token at christi's auction house because it was an encripted file whose record of ownership is publicly l on block chain. You can screen shot it, but it'll never be