http://www.theverge.com/2015/10/16/9548627/microsoft-trade-in-offer-windows-10-macbook

Microsoft will pay $200 for your old laptop, or $300 if it's a MacBook




Microsoft has launched a promotion called Easy Trade Up designed to get people to switch to new Windows 10 machines. If you buy a qualifying computer from the Microsoft Store for over $599 until October 20th, the company will give you a rebate after you send in your old laptop or all-in-one — you'll get $200 for a Windows computer, and $300 for a MacBook. Your trade-in computer has to be under six years old and in working order with a minimum display size of 11.6 inches. The offer is running in the US, UK, Canada, India, Brazil, France, Germany, and Taiwan.
This kind of promotion is a tactic Microsoft uses pretty frequently when it wants to juice sales. Recent years have seen the company offer $200 for iPads traded in against a Surface, $100 for PS3 owners switching to the Xbox One, $650 off a Surface Pro 3 in exchange for a MacBook Air, and $200 gift cards for a traded-in iPhone. The question with deals like these, as ever, is whether you'd get more money hawking your old device on Craigslist, eBay, or elsewhere; trade-in site Gazelle offers up to $539 cash for a MacBook Air, for instance.