The notional value of trading in 'cooking-pot exchanges' is immense even at present. Like the traded services themselves, it is intangible; but if one were to attempt to put a price tag on every Web site, free program and bit of advice offered on the Net, the market has a notional value of at least $100 billion. Of course if one were to try (as many do, by and large unsuccessfully) selling services at their notional prices, the market would collapse.
How long has "day trader" been in the vernacular, and already they have a special tax considerations for it. I would have to believe that congress will find a way to tax these guys just as soon as there are enough of them to catch its attention. Too bad congress can't move as fast on anything else. If congress ever bans unsolicited junk e-mail, I might be able to see them as something other than tax collectors. While they are at it, force broadcasters to use the same volume during commercials, damnit.