A practical way to compensate musicians?

These days purchasing music is pretty much a voluntary act of charity.  The listener decides if they'll pay. 

I think a number of ppl would like to pay some amount to the artists but not the amount the music's sold for.  Which means they end up just pirating it for free.  

They might pay something if it was an  amount they were comfortable with and doing so was super low friction. 

Since they'd only pay what they're comfortable with they'd have to set the price. 

I'm not talking about how things should be in an ideal world. But trying to see what is the best that can be done in the world as it is. 

You could incorporate a new feature into music playing programs like WinAmp and iTunes. When they installed they'd ask the user if they want to make a monthly contribution amount that'd be distributed amongst the artists whose songs the person plays. The user could enter in an amount they were comfortable with - eg $5. Obviously this'd have to be connected with something like pay pal or a credit card.  

The user would of course be able to later change this amount or stop the payments all together. 

The programs can track which songs by which artists the person plays (like plugins for things like last.fm currently do - in fact the scheme I'm describing could alternatively be done via a site like that). 

It'd then divide the monthly amount appropriately between those artists. Obviously there'd need to be infrastructure to get all these paymets to them. That'd probably be the hard bit to do.

This seems pretty low friction  Once it's set up the user doesnt need to think about it or think about how the amount of music they're playing is going to cost them.  The amount they pay is known in advance and is a flat amount that's the same no matter how few or many songs they listen to in the month.
 
It could be set up so a verified display of their contribution amount could, if they wanted, be shown on their facebook profile or whatnot, which might apply a little social pressure to others to contribute.  

Making these contributions the default on music players could harness the power of defaults.

And of course there's the potential to apply such a model to other media such as movies or newspapers.