What are the DSL Resale options?
Certainly, Covad/MegaPath, New Edge Networks, Qwest, IKANO, and Bandwave Systems. Mammoth Networks resells Qwest DSL in almost all the DSLAM's, but their CEO thinks the days of DSL resale is becoming more challenging. Hence, why Mammoth has turned to bigger pipe, like Metro Ethernet.
In the BellSouth DSL world, there were DSL Aggregation companies like ITO Group and Megapath, who sold DSL through the RBAN service.
BCN Telecom just expanded their DSL offerings - although I have no idea what kind of offering they have.
There's also cable - if you are in Charter territory or if you want to talk to the cable wholesale division. Just be aware that at some point, like with BHN, they will price retail lower than your wholesale offering as well.
Finally, you might look at 4G resell through BroadSky Networks or Clearwire.
But if you bring broadband to the underserved or unserved, you help a whole community.
UPDATE: Sonic.Net is also an option for AT&T DSL resale. Sonic.Net offers wholesale access both to AT&T in 13 states, and to its new CLEC ADSL2+.