In a move that's sure to irk many of its' customers who have come to expect a fixed monthly charge for unlimited data access, Time Warner says it plans to test a new pricing structure for high-speed Internet usage that charges subscribers based on the amount of content they download.

Under the proposed scheme, new customers in the city of Beaumont, Texas will be able to choose from a couple of different plans with varying bandwidth caps. An online tool will enable both existing and new subscribers to track their bandwidth usage, however, for the time being only new subscribers will be charged incrementally for bandwidth usage above the cap.

Time Warner says it wants to improve performance by creating a barrier for super heavy downloaders which, according to the company, represent only 5 percent of their subscribers but utilize more than half of the total available network bandwidth. Unfortunately, if not set high enough, these caps could also hamper the growth of perfectly legal but bandwidth-intensive services such as video-on-demand.