10 Mind-Blowing Easter Eggs Hidden in Famous Albums at Cracked.com. I knew about a few of these already: the Information Society thing, the Pink Floyd thing and the Beatles thing. The way I learned about the Beatles album was kind of funny. One night at work (back in the pizza restaurant days*), we were talking about albums (a frequent topic) and I said, "You know, it would be cool if someone made an album with two parallel sets of grooves, so you would hear a different bunch of songs depending on which groove the needle went into when you started the record." Answer: "It's been done. The Beatles did it."
I read somewhere about that Information Society album a long time ago. Possibly in the pre-internet days, I'm not sure.
*I dreamed I was working there again just a few nights ago...AGAIN--will I never stop dreaming about that place? This will mean something to one of you. Or possibly two of you.