Update: As of May 9, this discount code appears to be inactive. The card has returned to its full price.
Original story follows...
Xbox Series X and Xbox Series S both support expanded storage for playing next-gen games, which the PS5 does not, but doing so requires a proprietary storage card. Right now, that Seagate Storage Expansion Card for Xbox Series X|S is on sale at Newegg, giving you more than $20 off its regular price so you can install even more games. It's the only one that works right now, so you'll rarely find a better deal.
To take advantage of the 10% discount, all you have to do is enter the promo code 93XQY65 in the code field during checkout. This will give you the discount, which drops the price down to $198. Though that is still nothing to sneeze at, the card is the only one that supports direct play of Xbox Series X|S games other than the consoles' own internal storage. Currently, other external drives, including other SSDs, only support storing these games, and they must be transferred to the internal drive to play.
Designed in collaboration with Microsoft to ensure compatibility and performance, the Seagate drive is meant to offer the exact same experience you'd get running a game off the consoles' internal NVMe SSDs. That means support for Quick Resume and very fast loading times, and with 1 TB of storage, you can put a whole bunch of games on it.
It remains to be seen if any other manufacturers will release their own compatible expansion cards for Xbox Series X|S, but because that hasn't happened yet, we rarely see price drops on Seagate's model. If you're running out of space already and don't want to delete your favorite games, now's a great time to buy the drive. That's especially true if you're taking advantage of Newegg's recent Xbox preorder discounts, which have knocked off $10 on upcoming games like Biomutant.