When a song reaches the No. 1 spot on the Billboard Hot 100 chart, it's because the tune is fresh, original and ground-breaking, right? Not always. In fact, quite a few chart-toppers aren't just old hat -- they're old. These artists made it to the top with covers of others' songs, proving that doing something first is not the same as doing it the best. Check out 10 songs that have made it to the No. 1 spot on their appropriate charts as covers, and the originals that didn't make it quite as big: