(Disclosure, I may receive a small referral fee when you make a purchase through links on this post.)
If you are looking for an excuse to buy the Chromecast, this may be it. Google is offering $20 Play credit when you purchase the new Chromecast. Depending on where you buy your Chromecast, that makes it only $10-15 dollars! You can spend the credit on movies, apps, music albums, and more. To redeem, simply download the Chromecast app, from the left menu bar click “offers”. Your Chromecast must be installed and reachable from your app in order for the offer to be available. Google will ask you and check against the serial number to see what offers you qualify for. Make sure you understand the terms before agreeing to other offers. Some may be free for a period but start billing after expiration.