A new device will add some local color-but little else, say activists-to the black-and-white landscape of needle exchange. Developed by inventor Min Lim and lawyer Michael Marinangeli, the syringe has a chemical coating that turns blue 10 seconds after use. So what distinguishes it from the 500 or so patents for non-reusable needles? "It costs just pennies to make," Lim said. His syringes can be made without assembly-line modifications, whereas other one-use needles require major retooling to produce.

But prevention activists are underwhelmed. "This is a nonsense approach that doesn't address the real issue: People who inject drugs need access to sterile syringes," said Jason Farrell, of New York City's Positive Health Project, which runs a syringe-swap. The Harm Reduction Coalition's Alan Clear agreed. "The laws have to change, not the needles," he said, adding that DC and nine states require a doctor's script to buy needles, creating a fake shortage that leads to sharing and reuse.

Until the laws change, Lim and Marinangeli say, their invention will help health care workers avoid the accidental reuse of needles. Next up? Hmm...Condoms that squeak, "Use me"?