And I believe that most of the time, DSL is tiered pricing. In my area for instance, 1500/128 DSL cost $80/month, while the same cable speed (not tiered pricing) costs about $45/month if you rent the modem.
And not to offend you, w0lv3rin3, but both DSL and cable are referred to as broadband, along with satellite, wireless, and anything else out there that offers "higher bandwidth."