There's actually no shortage of B side tracks that went on to became of the most famous, favorite and popular songs in rock history. Sometimes even eclipsing the A side. [1][2][3]
Everything from Elis "Hound Dog", The Smiths "How Soon is Now" to Zeppelin's "Hey Hey What can I do." B-sides are/were often a chance for an artist to release something the record company rejected for the album but the artist really wanted to release. B-sides are actually often things for the fans.
As a counterpoint, here are the B-sides from that British quartet of yesteryear, most of which were only released as singles (until the discographies were published decades later). Some of these are better than the A-sides. YMMV.
P.S. I Love You,
Ask Me Why,
Thank You Girl,
I'll Get You,
This Boy,
You Can't Do That,
Things We Said Today,
She's a Woman,
Yes It Is,
I'm Down,
Day Tripper,
Rain,
Yellow Submarine,
Penny Lane,
Baby You're A Rich Man,
I Am the Walrus,
The Inner Light,
Revolution,
Don't Let Me Down,
Old Brown Shoe,
Come Together,
You Know My Name
The Anthology series is also a really good example of using archive material effectively. For example, you can see how songs like Strawberry Fields Forever and Day in the Life evolved over multiple sessions.
