[youtube=http://www.youtube.com/watch?v=7e5g8wXE__Y&w=700] An anguished love song John Lennon wrote to Yoko Ono, Paul McCartney interpreted it as a "genuine plea", with Lennon saying to Ono, "I'm really stepping out of line on this one. I'm really just letting my vulnerability be seen, so you must not let me down." Richie Unterberger of Allmusic called it "one of the Beatles' most powerful love songs", and Roy Carr and Tony Tyler called it "a superb sobber from misery-expert J. W. O. Lennon, MBE. And still one of the most highly underrated Beatle underbellies." The Beatles performed "Don't Let Me Down" twice during their rooftop concert of 30 January 1969, one of which was included in the Let It Be film, directed by Michael Lindsay-Hogg.

In 1969, Marcia Griffiths did a reggae version, which I adore:

[youtube=http://www.youtube.com/watch?v=1AJ_icsSzC4&w=700]  

There are other covers too -- Ben E. King, Annie Lennox, Stereophonics, a beautiful one by Paul Weller to name a few -- but one of my favourites is one I only just found out about, Phoebe Snow in 1977, with a syrupy, languid voice that tickles the back of my neck and tweaks at my heart:

[youtube=http://www.youtube.com/watch?v=p-SFzCzohrA&w=700]