The basic mouse has been with us for a long time now. They have been re-designed and re-modelled over the years, but some of us still find them uncomfortable. And continuous usage can lead to RSI (repetitive strain injury). If you have had that problem, then using a different mouse or using the other hand may help. However, as we are not all ambidextrous, we recommend using a Trackball or Vertical mouse. The vertical mouse completely changes the way you hold the mouse and puts your hand in a more natural upright position. By doing this it stops the bones in the forearm crossing over.