Since 1997, my computer-based communication system has been sponsored and provided by Intel® Corporation. A tablet computer mounted on the arm of my wheelchair is powered by my wheelchair batteries, although the tablets internal battery will keep the computer running if necessary.
My main interface to the computer is through a program called EZ Keys, written by Words Plus Inc. This provides a software keyboard on the screen. A cursor automatically scans across this keyboard by row or by column. I can select a character by moving my cheek to stop the cursor. My cheek movement is detected by an infrared switch that is mounted on my spectacles. This switch is my only interface with the computer. EZ Keys includes a word prediction algorithm, so I usually only have to type the first couple of characters before I can select the whole word. When I have built up a sentence, I can send it to my speech synthesizer. I use a separate hardware synthesizer, made by Speech+. It is the best I have heard, although it gives me an accent that has been described variously as Scandinavian, American or Scottish.