Hellmark, I would never forget! He's #3.
I can think of another, but it only works in conjunction with its alternate:
Amz1: IF YOU BUY A KINDLE, YOU CAN NEVER BUY FROM ANY EBOOK SUPPLIER BUT AMAZON.
Amz2: IF YOU BUY A KINDLE, YOU CAN BUY FROM
ANY EBOOK SUPPLIER YOU WANT.*
*note that it isn't mentioned that you will have to learn to love cabbages.
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Also:
Amz3: THE AMAZON EBOOK CATALOG IS BIGGER THAN EVERY OTHER EBOOK CATALOG IN THE WORLD COMBINED AND THEN MULTIPLIED BY FORTY-TWO.