The Beatles Rock Band is a game full of love and respect for the source material. Everything from the beautiful opening animation that follows the career of the band to the cuts of screaming girls in Shea Stadium has a level of design and care not often seen in the medium.
Even the Xbox Achievements for the game are named after Beatles songs, lyrics and trivia. The Day Tripper achievement is scored if you complete the entire game within 24 hours of play. If you score 100% on drums in Helter Skelter you get the "I GOT BLISTERS ON MY FINGERS!" achievement (nice touch on the all caps).
And my favourite comes at the very end of the game. After the rooftop concert is complete, John Lennon utters his famous goodbye and the "Passed the Audition" achievement pops up. And it feels good.
A full list of achievements for the game can be found here.