Wego Concerts, which arranges a date at a concert you'll both enjoy.
Fans connect to the free services through their Facebook page, and the app then probes your iTunes library to create a musical profile of you to make recommendations to concerts that you'd probably like to see. You have the ability to edit your playlists before anyone else sees them (which can be handy if you're a closet Justin Bieber fan), then you set your dating preferences - male/female, age, etc.
At that point you're able to browse through a range of people in your area with similar musical tastes. Users seeking dates have a heart surround by a pair of headphones so they can be easily identified, but you can look for other like-minded people to share the concert experience as well with no dating in mind.
One interesting thing that the app developers have found is that the romantic connection is deeper if the act they see together isn't that well known.
I'm not sure how they're monetizing this app, but anything that helps people go to shows can only be a good thing.