Groupon offers the factory-refurbished Google Chromecast Streaming Media Player for $20 with free shipping. That's $3 under our refurb mention from last month and $10 below the lowest total price we could find for a new unit elsewhere. It attaches to your HDTV's HDMI port and connects to your wireless network to receive streaming online video, music, websites, and more from your smartphone, tablet, or laptop. It also allows you to use your Apple or Android device as a remote. A 1-year Google warranty applies. Deal ends April 21.