A group of persons with a variety of neurological and mental impairments participated in a study to investigate the use of a mental interface and a trackball to point and click in a Windows 95 environment. Each participant's disability, medications, and performance with each input device are displayed. Some observations are made and discussed. The paper concludes with a participant using a newly modified version of the Yes No program to communicate. This person can use no other input device except using the Cyberlink to communicate or control a computer.