In a widely reported story, a Danish study indicates a no more than normal incidence of cancer among cell phone users. Unlike many other studies, this one involved hundreds of thousands of people--a number large enough to make it statistically reliable. Researchers caution that the we still don't have enough long term data to know for sure that cellphones are completely safe. There is widespread agreement that cellphone and cordless phone frequencies in the gigahertz range do cause measurable changes in cell activity. What we don't know is whether or not this causes health problems. In the meantime, I'll continue to use a wired headset as much as possible (Bluetooth wireless headsets use microwave frequencies, so they are not an improvement).