If it sounds like an April Fool's Day joke, guess again!

GameStop , the video game retail giant, is hosting a "Trade Anything Day" on Saturday, Dec. 6, where people can bring in almost anything to trade in for a store credit.

There are a few ground rules, however.

For one, the company says the item must fit in a 20-by-20-by-20 box.

So, if you were hoping to trade in your retro Sony Trinitron CRT TV from the '90s, you're out of luck (although you may find another customer willing to buy it).

GameStop also says you can only receive store credit on one traded item.

It's not yet clear how the approximate trade value of each item will be determined... but consider us intrigued, and willing to give just about "anything" a try!

See below for additional details.

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