If you want full freedom of movement, you should opt for a wireless mouse such as this one. While most computer mice have two buttons (and maybe a scroll wheel), this one has seven
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Adesso 2.4Ghz Wireless Programmable Ambidextrous Ergonomic Trackball Mouse, with, Black, iMouse T50
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IMOUSET50 - iMouse T50 Wireless Ergonomic programable Desktop Trackbal
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