Add a thumb key My first foray into the world of alternative keyboards was this simple modification to my obsolete Qwerty keyboard. Frustrated with frequent typos and losing the home keys when I backspaced, I came up with this idea of a thumb-operated backspace. I cut a hole in the wrist rest of my Adesso Tru-Form keyboard. Under the cut-out piece, I mounted a lever switch wired to the original backspace key. The original key still works too.