Since most modern computers use a form of mouse control, one of the most critical accessories is a mouse mat. Mice are designed to be moved across a flat surface, and the type of surface the mouse is used on has an affect on how well the mouse works. For example, using a conventional computer mouse containing a roller ball on a rough surface will make controlling the on-screen pointer very difficult.
If you have a sound card in your computer, then the type of speakers you have will dictate how good your computer sounds. If you regularly play music and watch DVD movies, then you will probably want a good set of speakers.
You can also obtain different styles and designs of keyboard, accessories for your mouse, dust covers for your monitor, and extra devices like printers and scanners to help you create document, print letters, organise your photographs and make your computer easier to use.