Celebrity dalliances and secret trysts aren't something we normally talk about on this blog. It's much more fun to discuss the drama in the stock market (for us, at least).

But still, it's hard to avoid the Tiger Woods news this week, and I wonder how much this painful episode will cost him and his sponsors.

Tiger Woods is a major corporation unto himself, with Sports Illustrated estimating he gets nearly $100 million a year from commercial endorsements and other initiatives. The Daily Beast guesses he's made about $1 billion in his career pitching products.

Up to now, Woods has been relatively scandal-free. Will the uncomfortable public revelations -- and the women who claim links to him -- put the pinch on his pitching?

Woods will probably still maintain his agreements with Accenture (ACN), a major sponsor, and the video game publisher Electronic Arts (ERTS), writes Gerald Posner of The Daily Beast. A golf course development company, Tiger Woods Design, is also safe.

But what about Nike (NKE) or Gatorade? Gillette? AT&T? Most of these companies have confirmed support of Woods, but if the scandal continues to drag on they may need to rethink that.

Even if Tiger takes a 10 percent hit on his endorsement income going forward, that’s $10 million a year, or $100 million over the next decade. A very expensive domestic incident.

SmartMoney gets even more specific with its "Tiger Trouble Index," which looks at the stocks of companies linked to Tiger.

Here's how their shares have performed over the last week. There doesn't seem to be much impact:

Nike: Shares pretty much unchanged, in the $65 range.

Accenture: Shares up slightly, from $40.58 to about $41.79

Electronic Arts: A slight drop over the week, from $17.51 to about $16.87.

Pepsi (PEP), which makes Gatorade: Unchanged

AT&T (T): Unchanged

Chevron (CVX), which saw Woods back out of hosting its World Challenge Tournament: A slight drop from $79.64 to about $78.49.

Woods is taking the rest of the year off, but if he continues to keep a low profile in 2010, that will mean more missed opportunities for his sponsors. After all, as MSNBC's David Sweet writes, "there's no payoff when the pitchman is invisible to the public."

But who can blame him for wanting to be alone with his family? The best way out of this circus is quality time at home with his wife and kids, away from the prying eyes of the media and gossip-mongers. And you can't put a price on that.