The manual sorting of thousands of Drosophila embryos necessary to isolate homozygous mutants is both laborious and time-consuming. On page 153, Furlong et al. provide a solution, constructing a fluorescence-activated embryo sorter based on embryo expression of green fluorescent protein (GFP). The machine can automatically sort 15 embryos/s with better than 99% accuracy and has been adapted to sort embryos of other species as well. In addition, Furlong et al. have made available online the detailed plans for their machine.