Max MP is having a New Year Sale, dropping the price of Poweramp (described as the “most powerful music player available on the Android OS”) to just 60 British pennies, or "60p" if you prefer.
Poweramp has been the #1 paid music player on Google Play three years running. Usually £2.50.
Requires Android 2.1 or above.
(Thanks to Third_Degreee at HUKD)