Bacteria and viruses beware -- Trojan Technologies wants to zap you. The company manufactures ultraviolet (UV) lighting systems for disinfecting wastewater and treating contaminated soil and groundwater. Trojan's wastewater treatment systems are used in about 4,000 municipalities in 50-plus countries. The company's UV light systems work by altering the DNA in microorganisms and are an alternative to traditional chlorine-based disinfection systems. Trojan also makes UV products that cleanse water used in industrial processes such as food production and electronics manufacturing. Other products include residential UV systems for drinking water. Danaher controls Trojan.