Flying Blue, the loyalty programme of Air France and KLM, has an online shopping portal called Shop for Miles.
Similar to BA eStore and Topcashback, it’s a cashback-style website where you earn a rebate for purchases referred by them.
As a new customer, you also earn 500 bonus miles for your first purchase, on top of your regular rebate. 500 miles is not much, but may be handy if you are a few miles short for an award redemption. It should also extend the expiry of your miles.