For obese people, gastric-bypass surgery is a risky gamble to shed major pounds. Now a safer alternative is on the way: the gastric stimulator. In a reversible procedure, doctors implant Medtronic's matchbook-size Transcend II stimulator just under the skin in the abdomen. Once in place, the device sends a painless electrical pulse into the stomach wall about every six seconds. The electricity relaxes and distends the stomach, conveying signals to the brain that trigger feelings of satiety. Doctors can adjust the frequency of the pulse&8212;and thus fine-tune the patient's hunger levels&8212;by simply waving a wand over the gut.