Today only at Amazon, purchase a select Album on CD or Vinyl and bag a $20 Amazon Music Unlimited Credit for free. (Qualifying items will show "Buy a CD or Vinyl and get $20 credit towards a Amazon Music Unlimited Plan" if you scroll down and look beneath the Special Offers and Product Promotions heading.) Plus, if you're new to Amazon Music Unlimited, you can also take advantage of a 30-Day Trial for free. As this service costs $7.99 or $9.99 per month (for Prime members or non-members, respectively), that's a minimum of two months' worth of free music, and the best such deal we've seen. Click here to learn more about Amazon Music Unlimited.