Abstract: A combination handheld mobile telephone and wireless mouse for navigating a Windows®-based operating system of a computer comprises a telephone battery that is transformed to accommodate the electronics of the mouse. The mouse is attached to the telephone by connecting means that replaces the original (old) telephone backing or housing with the mouse. The telephone battery is modified to provide electrical contacts, preferably on the side opposed the side that employs electrical contacts to power the telephone, to power the mouse. In this regard, the combined mobile telephone and wireless/optical mouse can run simultaneously, both drawing and sharing power from the same telephone battery.