Keeper let us know about his latest BlackBerry app creation Music Timer in the forums. The new app is available for both BlackBerry 10 along with current OS 5.0+ BlackBerry smartphones. The app is essentially an MP3 player with support for all the audio current BlackBerrys can play along with one useful function. It allows you to set a timer like a sleep timer to stop the music after a certain amount of time has passed. I have quite a few friends that could use such a function for podcasts or listening to music before going to bed.
You can find the BlackBerry OS 5.0+ version for download OTA in the forums from Keepers post. The Music Timer X for BlackBerry 10 is also available now and you can pick it up free from Mediafire and sideload it or it is available for $0.99 in App World if you have a Dev Alpha. It has similar features with more coming soon. Check out the details in the forums.