Dear Future Self,
I hope this letter finds you well and still fitting into the pants I own here in the past. Your world must be an amazing place, full of technological wonders and marvels. Maybe you have even eradicated some of the problems of my world, like air pollution or Time Warner Cable.
I write, however, to ask that you please set aside the sum of fourteen dollars and ninety-nine cents (or the equivalent in your future currency) for the purchase of this valuable item:
Yes, that is what dogs and wolves look like in my time - as if they have just eaten a very, very, very old piece of beef. I know not when this shirt will be available to you over the Internet, but I trust that you will respect our wishes and buy this, that you may wear it proudly in remembrance of my simpler, stupider time.