While there are 144,000 discovered species of fungi on the planet, there could be many more—millions more, in fact. But finding fungi and sorting out whether or not they contain any useful chemical compounds comes down to chance. The serendipity, scientists argue, is what led to great discoveries like penicillin—so hope for similar-level finds persists. Recent tests may have uncovered compounds that can help create biofuels, life-saving medicines and even limit the pollutants in animal waste. See how these experiments are conducted and how new species are discovered at CNN.