'Motley Fool' Brothers Get Serious about Business Plans.

Byline: John Zebrowski

Sep. 21--Tom and David Gardner are being serious.

The funny hats are safely squirreled away; their humor turned down a couple notches. Instead, the founders of the personal-finance-information company Motley Fool discuss business models; their new chief executive, Pat Garner, sketches a graph on a napkin to explain how the company has refined what it does, emphasizing what is profitable, jettisoning what isn't. It's strange to be hearing this from grown men who are famous in the Internet world for comparing themselves to well-heeled clowns.

But now is not a time for tom-foolery, if you'll pardon the pun. The days when any company could jump on the Internet and expect investors to throw money at it like beads at Mardi Gras are over. After the party comes the hangover.

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