If someone had come up to you and said "Hey, can I have a couple cardboard boxes? I need to pack some stuff to send to a friend." you may have given the Xbox box to him. In this case though, since someone offered you so much more than you may have originally thought the box was worth, your perceived value of the box has gone up. Now you think it may be worth even more, or it's some sort of collector's item, or something like that....maybe?

Just wanted to let you know, I believe that with Impulse you can "Archive" any game you have downloaded / installed (or update for a game), to be installed in the future. From what I understand, Impulse may still need to connect to their servers to verify you own the game, however they are working on "Impulse Anywhere" (see http://anywhere.impulsedriven.com/ which sounds like it will allow you download an offline installer for the games you've purchased.

I can has achievements? Time to achievement whore!