If The White Album showed The Beatles fracturing into four distinct musicians, Abbey Road is them working together as a single, harmonious unit once again. However, that was not the case behind the scenes. While this was the last album they recorded with the full band, Lennon refused to participate in a couple songs (he's absent on "Maxwell's Silver Hammer") and privately left the band for a time during the session. Paul would publicly do so a year later, ending The Beatles. Released in September 1969, Abbey Road, with it's iconic cover, reached #1 on both the US and British charts.
My comment about them working together is in reference to the B-side of this record. Starting with "Because", the songs that finish the album flow seamlessly together. My only gripe is tacking "Her Majesty" on the end of it. If the album ended with "The End", it would have been perfect. I could cheat and post a the entire B-Side, but I won't.
The best song on the album is George's "Something", which he wrote for his wife Pattie Boyd. Side note: Boyd left George Harrison to marry Eric Clapton. She served as inspiration for the song "Layla" and possibly "Wonderful Tonight". What was it about Boyd that inspired such great music?
As far as lesser known songs, I like "She Came in Though the Bathroom Window" and this week's song "You Never Give Me Your Money".
Here's a demo version of "Money":