New York magazine's discovery of the week is "the half-hooker economy" -- typified by the nebulous semi-pro status of many of Tiger Woods' bevy of mistresses. The half-hooker is not technically a prostitute, but in the VIP world of nightclub bottle service, she is available for sex in exchange for gifts, financial help or in the case of a celebrity encounter, status.

But is there really such a thing as a "half-hooker"? We asked Tracy Quan, a former call girl who says she has occasionally passed for a semi-pro herself.

Ten Things You Should Know About the Half-Hooker Economy

10. Ever since the first self-important cavedude boasted that he "never pays for it," there have been "lite-hooks," "models," party wenches and so on who "don't charge for sex." But sex does happen, the rent gets paid -- and 21st-century bottle clubs are part of an ancient tradition.

9. Role models abound in vintage chick flicks like "Breakfast at Tiffany's" or "Gentlemen Prefer Blondes": money for the powder room, diamonds for a rainy day.

8. Today's bottle girl doesn't want to be mistaken for an "escort," but what do you think the half-hookers of an earlier time were called? That's right -- escorts. Only the names have changed.

7. A real hooker will sometimes pretend to be a half-hooker, but it's unheard of for a lite-hook to pretend she's a pro.

6. Most escorts think the half-hookers look a little out of control. A real hooker is less likely to dress like one, even when she's working.

5. Nice girls do ... charge for sex, that is. Does she spend her me-time studying to be a vet? Reading highbrow fiction? Crafting? Cooking pies, helping Haiti, trying to change the world? These are style signifiers of a real hooker. Half-hookers shop more, read more gossip and are less concerned with burnishing a politically correct image.

4. But those high-heeled cartoon monsters in the New York cover story (who won't look at a guy unless he's making a total fool of himself) aren't the only game in town. Believe it or not, there are classy approachable half-hookers who think $3,000 is an idiotic price to pay for a bottle of champagne. They go to museum benefits and upscale housewares shops to meet their half-customers -- places where you can hear a guy talk.

3. Real hookers do go to bottle clubs, but only to have fun or amuse their dates, and not every night. Probably not even every week.

2. It's easier to introduce a real hooker to your family, whether by accident or on purpose, because she knows exactly what she's hiding, who she's hiding it from -- and why.

1. "Rachel Uchitel is not a madam" means this: Rachel Uchitel is not a felon. Half-pimps and half-madams stay more than one step ahead of the law, avoiding the fate of Jason Itzler, a founder of the now-defunct New York Confidential escort agency. (Itzler proposed to his favorite call girl, Natalia, while doing time at Rikers Island.)

For more Tracy, buy "Diary of a Manhattan Call Girl" now.