Taking a cue from the Mexican Deluxe coaches, there is now anew, more upmarket bus service including WiFi that travels between Washington DC and Boston, via New York.
NYC-DC and NYC-Boston for $15 (and some early buses as low as $10)
At these rates, they may end up putting the competing chinese bus services (which have a shaky safety record) out of business. (and of course the BoltBus fares are likely to increase substantially if that happens.) The service is owned by Greyhound, but renamed as BoltBus (presumably to avoid any negative associations with Greyhound).
Read all about it in this Times UK article: