Edit: just discovered we do actually have a phone we can use for this, so never mind!

If you wanted to wake a child up with an alarm clock that played your choice of music.. how would you do that, if you didn't have a spare smartphone lying around? Would you DIY something along the raspberry pi line? Do you know of an off the shelf alarm clock that would work?
Bonus points for either very cheap, or not so cheap but like ... Ethical in an open source kinda way?