There are all kinds of strange things on YouTube. For instance, this recording of Erik Satie’s notorious “Vexations.” Normally a complete performance runs from 14 to 24 hours. Nicholas Horvath plays the 840 repeats in less than ten hours, which is blazingly fast for a piece marked “très lent.” (No, I’m not counting them, and I don’t expect to listen to the whole thing.) On another occasion, Horvath took 35 hours to play the piece. That performance was probably closer to the proper tempo.
Not every pianist who attempts a solo “Vexations” succeeds. From The New Yorker:
An Australian pianist named Peter Evans abandoned a 1970 solo performance after five hundred and ninety-five repetitions because he claimed he was being overtaken by evil thoughts and noticed strange creatures emerging from the sheet music. “People who play it do so at their own peril,” he said afterward.