Lady Gaga covers John Lennon's 'Imagine' and 9 other amazing celebrity covers

Thanks to YouTube, millions of unknown artists have shown off their impressive vocal chops. Some sing original songs,while others do covers of famous artists. Sometimes, these individuals even score record deals from uploading their best work. Remember a once-undiscovered Justin Bieber?

What's even better is when well-known artists perform covers from of their favorite songs. Lady Gaga recently performed John Lennon's ''Imagine" for the Baku Games 2015 Opening Ceremony and had us thinking, what other celeb covers are out there?

Click through the gallery below to see our top 10 best celebrity covers of all time!

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