DSL.net which is now part of MegaPath deserves a special mention on these pages because it appears that they are the last semi-major SDSL provider who operates Copper Mountain DSLAMs. We haven't been able to find out the exact extent of the old DSL.net service footprint, but it appears to be very small unfortunately, covering the major metropolitan areas on the East Coast between Boston, MA and Washington, DC and not much else.
When providing SDSL service in geographical areas not covered by their CM-based DSL.net footprint, MegaPath goes through Covad like most ISPs.
Harhan Engineering Co. has got a channel partner arrangement with MegaPath, and we are now able to assist end users with procuring some of the more unusual services like SDSL with V.35 hand-off or bonded SDSL up to 12 Mbps symmetric. See this page for more information.
MegaPath has also made some contributions to our project which we gratefully acknowledge: