I still can't tell you how I feel about the cancer. But I can tell you about Intuitive. Its stock jumped more than 50 bucks Wednesday, after the Sunnyvale, Calif., company reported better than 50% growth in June-quarter sales and once again beat earnings estimates. At 322 each, the shares now go for more than 75 times trailing 12-month earnings, giving Intuitive one of the handsomest multiples in the Standard & Poor's 500. That multiple reflects the alacrity with which surgeons have adopted the company's da Vinci robot, a four-armed marvel the doctor controls from an operating-room console. Patients have less bleeding and scarring, and can get back on their feet without a long, expensive hospital stay. But Intuitive's volatile and pricey shares also bespeak the desperation of investors mobbing a quality growth story in a lousy economy and stock market. That momentum mob seems heedless of how suddenly this expensive stock could become a victim of the robot's success. You can gauge the market for robotic surgery better than you can for some other new technologies...like Google's, for example. About 40% of the country's large hospitals already have at least one da Vinci robot. When Intuitive (ticker: ISRG) finishes placing its robots, it will see a falloff in the systems sales that have contributed more than half of its revenue. Sales of disposable instruments and accessories for each operation will continue, but the growth rate of those revenues will also decline once the da Vinci gets its share of the relatively fixed number of surgical procedures performed each year.

Geox's stocks has tumbled 60% in the past year, to a recent €7. A 15%-20% gain in annual sales and profits could propel the shares to €9- €11 in two to three years.

The beaten-down shares could surge by more than 40% as the company resumes reporting full financial results, regains a listing on a stock exchange and boosts earnings.

Emerging exploration plays can be volatile. (Northern Oil surged last week on news that it had participated in three successful wells, bringing its total to 11, then quickly fell back.) Remember Denbury Resources, which soared on oil hopes in Mississippi, then treaded water when investors hot-footed it to the Bakken? "They can only really seem to comprehend one play at a time," says Bob Gillon, energy specialist John S. Herold's research director. Gillon doesn't watch Northern closely, but cautions that it doesn't own its wells. It leases land to operators in exchange for production royalties of 3%-to-37% (with an average working interest of 10%) and with little control over output. Shale's low permeability means production is often lower than it initially appears.

Since 1986, there have been 26 oil bear markets, defined as a 20% decline from the peak, according to Bespoke Investment Group, with the average lasting 125 days and producing a 32% decline in the commodity. Meanwhile, the S&P 500 typically gains about 6% during an oil bear, and we've already achieved much of that in the most recent rally. Not surprisingly, consumer stocks perform the best, energy shares the worst. To play petroleum directly, there are several ETFs to choose from, like the MacroShares $100 Oil Down (DOY), which rises when NYMEX light sweet crude futures fall, or, for bulls, the United States Oil Fund (USO), which moves up when crude does.

Since 1986, there have been 26 oil bear markets, defined as a 20% decline from the peak, according to Bespoke Investment Group, with the average lasting 125 days and producing a 32% decline in the commodity. Meanwhile, the S&P 500 typically gains about 6% during an oil bear, and we've already achieved much of that in the most recent rally. Not surprisingly, consumer stocks perform the best, energy shares the worst. To play petroleum directly, there are several ETFs to choose from, like the MacroShares $100 Oil Down (DOY), which rises when NYMEX light sweet crude futures fall, or, for bulls, the United States Oil Fund (USO), which moves up when crude does.

The drubbing left the one-time high-flyer -- flagged here in October as over- priced -- down nearly 56% this year. At about 66, shares now fetch just over 20 times forward earnings, down from a jalapeño-hot 53 times last fall. One analyst after another surrendered and downgraded the stock last week, worried about compressed margins and slowing growth as menu-price increases failed to offset the surging cost of ingredients. It doesn't help that the jalapeno has joined another key ingredient -- tomatoes -- on the salmonella-scare list. Sometime soon, a better risk-reward profile will nudge Chipotle onto the Buy list. After all, sales and profits are still growing, and the company plans to open more restaurants this year than it did last. But one senses the selling could get worse before the bears exact their toll and things get better.

Yum Brands (YUM), too, recently saw second-quarter revenue rise 12% and net income improve 4%, but alas, commodity costs pushed expenses up 14%. While the operator of KFC and Taco Bell beat estimates (thanks to a lower tax bill), its weakening margins worried investors enough to knock shares down to 34, off 16% since May. Considering the unprecedented pressure on consumers, its same-store sales look commendable, and 14% growth in China and plans to open 450 restaurants there helps Yum capitalize on the overseas consumer boom and the Third World's sad but growing hankering for American fast food. In 10 years, Yum reckons 70% of its growth will come from overseas, which makes this pullback a buying opportunity -- especially if the rabid rise in commodity costs begin to ease.