The dominating role of the mouse in modeling Alzheimer's disease has been challenged this year by Drosophila melanogaster. Transgenic flies expressing toxic beta-amyloid peptides develop neurodegeneration. It is these peptides that accumulate in human disease and are thought to be the initiating factor in Alzheimer's disease. The flies exhibit a clear phenotype from a few days of age, including reduced locomotor function, impaired olfactory memory and shortened lifespan. Therapeutic agents that interfere with the generation of toxic aggregates of beta-amyloid peptides have been shown to rescue the flies. Several groups are now using the power and speed of genetic screens in the fly to accelerate the discovery of novel therapeutic agents.