Lay science article about drug repurposing published in InScience Magazine. Drug repurposing significantly accelerates the discovery and development of drugs with a substantial impact on rare diseases. In collaboration with big data and artificial intelligence (AI) technologies, it enhances the reliability of predictions, regarding the effectiveness, but also the toxicity of the repurposed drug. Modern computational tools now guide and enrich laboratory approaches, while the latter validate working hypotheses or create new ones. A typical example of innovative synergies is the drug repositioning platform Cloudscreen©, an innovation product of Cloudpharm PC, a Greek start-up company, and the Biomarker Discovery & Translational Research Laboratory of the National Research Foundation.