Before we share the interesting story behind the logo design, let's play a quick quiz - try to guess the correct Amazon logo from these very similar designs. [hint: Amazon wants to provide every item on their online shopping store]
Well, the actual Amazon.com logo is the one on the bottom right corner. As you would have noticed, the logo has a yellow arrow between the first A and the Z letters.
The yellow arrow implies that they have everything from A to Z and also represents the smile on the customer's face. [Thanks Abhijit, Picture Credit: Guess The Logo]
Update: Peter Dawson has dissected the FedEx logo design and found a forward looking arrow embedded neatly between the letters "Ex".
Update: Ravi has compiled another good collection of corporate logos and their interesting backgrounds. The Microsoft logo has a slash between the o and s letters to emphasize the "soft" part of the name and convey motion and speed.