Did you know that the metronome, a clever device for marking musical tempo, wasn't widely patented until 1815 by Johann Maelzel, even though similar mechanical beat-keepers had tinkered around before? Interestingly, Ludwig van Beethoven was so impressed that he became one of the first prominent composers to embrace it, diligently including metronome markings in his scores and forever changing how his music was interpreted. His endorsement truly helped popularize this essential tool for musicians worldwide.