But the flat-rate plans are still popular.

Moreover, ISPs argue that existing flat-rate plans do not enable them to cover the additional cost required to manage heavier network traffic.

One of the attractions of a flat-rate plan is that it simplifies tax returns and, to illustrate the point, Perry held up a postcard size form.

The popularity of that plan, in turn, is setting off a frenzy among other wireless providers to offer their own flat-rate plans.

America Online introduced its $19.95 flat-rate plan at the end of 1996.

The advantage is that MCI's offer is a 24-hour flat-rate plan.

Some national cell-telephone companies are building business today by advertising simple flat-rate plans instead of nickel-and-diming customers with extra charges.

In spring 2004, au became the first cellular phone based data service provider to offer an unlimited use flat-rate plan in Japan.

Last week, for instance, Cablevision introduced a flat-rate plan that includes 500 minutes of calls to any foreign country for $19.95 a month.

The flat-rate plans are attractive, but people with very specialized calling patterns may find a package better tailored to their specific needs.