(FORTUNE Magazine) – America's wallet is getting lumpy, not with cash but with telephone calling cards. At least 15 different kinds are now available. In May, Western Union Financial Services began selling a disposable card available in $5, $10, $20, and $50 denominations. At the end of each call, placed over MCI, an automated voice lets callers know how much credit is left. In their fierce battle for market share, AT&T, MCI, and Sprint are trotting out lots of new features, conference calling, cards in Braille, and fax mailboxes, which allow cardholders to route all their faxes to a single number for easy retrieval. The breakthrough that many customers are waiting for, though, is technology that will reduce the number of buttons they have to strike to call long distance -- currently about the same number of keys required to play a piano concerto. -- J.M.

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