Since I've been talking a lot about Cable TV on BoingBoing over the last two weeks, the topic of why Cable TV was started in the first place has come up a lot. If you're wondering, here's an excerpt from About.com's history of cable:
Community antenna television (now called cable television) was started by John Walson and Margaret Walson in the spring of 1948. The Service Electric Company was formed by the Walsons in the mid 1940s to sell, install, and repair General Electric appliances in the Mahanoy City, Pennsylvania area. In 1947, the Walson also began selling television sets. However, Mahanoy City residents had problems receiving the three nearby Philadelphia network stations with local antennas because of the region's surrounding mountains. John Walson erected an antenna on a utility pole on a local mountain top that enabled him to demonstrate the televisions with good broadcasts coming from the three Philadelphia stations.
Walson connected the mountain antennae to his appliance store via a cable and modified signal boosters. In June of 1948, John Walson connected the mountain antennae to both his store and several of his customers' homes that were located along the cable path, starting the nation's first CATV system.