Box of Tomorrow rewards

Note that these boxes are susceptible to the fill-your-inventory glitch.
Meaning, it does not check that you have space in your inventory before generating a reward. It generates a reward, tries to give it to you, and only if it fails it says "check your inventory".
So, if you fill up your Use inventory, and still have that 2AEE coupon there (and non of the lame Use prizes), you can retry clicking on the box until it gives you another 2AEE coupon - or a Coin, or a Cash Shop item.

Someone give this man a medal.