NPR is where it's at

Bob Lefsetz is always talking about the reach of National Public Radio in the US.
It should be of great interest to all artists because it is egalitarian and you have a chance of having your music picked up and played on one of their shows ('All Songs Considered' is probably your best target for new indie music of any genre) - which may be syndicated across nearly 1,000 local community radio stations across the States.
It's even better than that as most of the shows are released online as streams or podcasts.
I'm not saying that radio promotion of any kind is easy for the DIY musician in the US, but there are little chinks of light that you should go after.
Bob says this:
Whenever I’m on NPR, I hear about it multiple times, for months thereafter.  From people I haven’t seen since college, from people who care not a whit about the music business.  My mother will call and say her octogenarian friends heard me testifying.  Which is all a long story to tell you when NPR comes-a-knockin’, SAY YES!
Read his view in this piece here.