Microsoft is offering 10% off (Up to $200) at eBay. Use it up to 20 times and up to a max of $2500.
Be sure to read the fine print!
For example “Purchase an eligible eBay.com Buy-It-Now item using PayPal within 60 minutes of the time you began the online session. Cashback Rewards will apply only to the first eligible item you commit to buy during an online session. You may make only one qualifying purchase per online session.”