I’d love an app/website where I specify my city, and then it plays me a streaming radio station composed of songs by bands/musicians that are playing a scheduled concert in my city in the future. This would expose me to new music and I imagine I’d buy some concert tickets to shows I didn’t even know were coming to town that it turns out I like.
Bonus: Allow me to filter it for today only, or next 3 days, or next 7 days, or next 30 days.
Bonus: Suck in my iTunes library file, and/or Hype Machine account, and/or last.fm account, and then mash this data with ‘related artists’ in last.fm, and tailor the radio station to similar artists you know I already like.
I find that there is no comprehensive concert calendar sites, but some are Pollstar, Songkick, Last.fm, Facebook, SonicLiving, Jambase, Eventful.