For Verizon customers only, Amazon offers an Amazon Music Unlimited 30-Day Trial bundled with 1GB Bonus Verizon Data for free. (Enter your phone number to check your eligibility.) That's roughly an extra 125 songs on your data plan for the month of the trial at no extra cost. (A bonus gigabyte of data costs $10 from Verizon direct.)

Note: The Amazon Music Unlimited subscription will auto-renew at a monthly rate of 14.99 per month; be sure to cancel your subscription before the trial is up to avoid extra charges.