Researchers have launched an ultra-large virtual docking library expected to grow to more than 1 billion molecules by next year. It will expand by 1000-fold the number of such “make-on-demand” compounds readily available to scientists for chemical biology and drug discovery. The larger the library, the better its odds of weeding out inactive “decoy” molecules that could otherwise lead researchers down blind alleys. The project is funded by the National Institutes of Health.