Google on Tuesday added a feature to its popular search tool that allows visitors to
calculate mathematical equations. It can compute basic arithmetic like 15*5+2, more complicated equations and measuring unit conversions like 200 miles in kilometers. Still, Google's calculator lags other rival services, including Overture-owned AlltheWeb.com, which has offered similar capabilities for months.
Mountain View, Calif.-based Google also introduced a tested version of its new toolbar, which lets people block pop-up ads or automatically fill in online forms.