This TP-Link smart plug costs $10 instead of $27 if you buy it with Amazon's Alexa

PCWorld 

Amazon's got a great deal for smart home users today, but you can only get it if you're part of a special club. Anyone who has an Echo device or a third-party Alexa-enabled device can get a TP-Link Kasa Smart Wi-Fi Plug Mini for $10 with coupon code SMART10. The bad news is Amazon's sale is limited to one device per customer. TP-Link's Kasa devices are already great options for smart home rookies since they don't require a hub, instead connecting via the Kasa smartphone app and Wi-Fi. The Kasa Smart Wi-Fi Plug Mini HS105 works with Alexa devices (natch) as well as Google Home, though only the Alexa-enabled get today's discount.