Web trading is arriving in time for the many large companies already racing to sell shares directly to the public. In the last year, the number of firms offering broker-skirting investment programs has tripled to 94, and the pace is picking up. “I expect 500 or 600 by this time next year,” says Jim Volpe, who monitors such plans.

While no one is selling shares on the Net just yet, the mechanics are in place and investors are starting to show some interest. Just ask Gordon Garney, director of shareholder services at Mobil Oil Corp. In the four months since the company posted a prospectus and order form on its Web site, about 975 investors have downloaded the form; that’s roughly one for every seven “hits” on the Mobil site.

Where is it all leading? Most likely, to dozens of mini-markets. SEC Commissioner Steven Wallman sees whole new trading systems evolving as start-ups, consumer giants and Internet intermediaries try to capture dollars from traditional transaction-fed brokers. Nasdaq executive John Wall worries that the day is fast approaching when your Windows software opens with this button: “Like Microsoft? Click here to buy 100 shares!”