Although they've arguably done more to promote peace and harmony than any other rock group -- heck, probably than another four people in history -- the breakup of the Beatles certainly resulted in its share of public bickering and lawsuits.

Paul McCartney broke many fans' hearts by announcing he was leaving the group in 1970, but reportedly John Lennon had already announced his departure to the band, and all four members had grown frustrated with their roles over the years.

The formerly unified (and peerless) songwriting duo soon turned their pens and talents against each other, trading barbs with solo songs such as McCartney's 'Too Many People' and Lennon's 'How Do You Sleep.'