Derek Webb albums are $5: Ctrl | Feedback | The Ringing Bell | Stockholm Syndrome | Mockingbird | I See Things Upside Down | The House Show | She Must & Shall Go Free
Amazon has 50 classical albums for $1.99 each.
Google Play is trying to get your attention with 48 albums for $2.99 each. Some goodies like Radiohead & U2. Also, various genres represented.