Wal-Mart is currently testing an automated video game trade-in kiosk at 77-stores in the US. It lets gamers redeem “the trade-in value back to a credit card, which takes 2-3 days, according to the instructions on the company’s website.”

e-Play has confirmed that they themselves set the trade-in prices based on a proprietary algorithm that can change as regularly as daily based on a number of different factors.

[via Kotaku]