No cable modems where I lived. I worked for an ISP and we'd order fire alarm circuits then just put SDSL routers on them instead. Up to 2Mbit speeds depending on how far from the exchange you lived, I was only able to get 512Kbit reliably. We were selling them to customers at a nice markup for a profit.

British Telecom wised up to it a few years later when they started marketing ADSL themselves and started filtering our traffic, but for a few years it was a super cheap way to get broadband if you had the know how.