If you're looking for something that's that much higher traffic, you'd need a high-speed "business" class DSL line that includes an agreement to host DNS for you (or allow you to host DNS). At that point, it would probably be a much better idea to pay for a colocated server from any one of the presence providers/hosting services out there so that they could take care of your hardware/software needs and you could just concentrate on actually building the site. In addition, downtime ceases to become your responsibility (business DSL only guarantees uptime of your connection, not of your servers) and chances are, your connection to backbone and thus to your viewers would be more stable (many of the better hosting services are connected directly to major backbones instead of routing through several 'jumps' -- which would mean there are less chances of a router/connect going down for one of your viewers).
~Ladi