A lot, actually, including the fact that only two covers of Beatles songs have ever reached number one (you can find out which songs in Thomas Beller's piece). (bookpage.com)
An Amalgam of all 4 Beatles in about 1965. (fadmagazine.com)
Somehow through some deal with demonic forces, Rock Band was able to make a version filled out entirely with Beatles songs (a feat I find difficult to imagine considering how tough it can be to get those rights). (toy-tma.com)