For those who don't know, In The Game and Upper Deck both have booths at the Expo. They don't sell product there, but during the Expo, you can line-up at the booths and when you get to the table, you open your box of cards. When finished, the company representatives will take your wrappers and you will randomly receive a short-printed card made especially for the weekend. Some times it's an autograph, other times it's memorabilia. You can usually open one box per day at the booths.
I was especially lucky at the Upper Deck booth last year and received these cards on Friday and Saturday:
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It's a great bonus for those who can make it to the Expo. It's great for the dealers too as it encourages more product to be sold and busted. I'm not 100% sure on the products which can be broken at the Expo as ITG has released their list but Upper Deck has not so I'm taking a guess on the Artifacts and the UD Series 1. Regardless, these boxes will be busted in a few weeks... free cards or not.