
The Mighty Mouse has an awful default button mapping. First off, both right and left button are assigned to left-click (primary). Secondly, for some inexplicable reason, clicking the scroll wheel brings up Dashboard. Third, I find the scrolling to be much to slow for my needs.
To fix these problems and any other issues you have with the button layout, open System Preferences and click on Keyboard & Mouse. Then fiddle with the button-mapping as much as you like. Currently, I have it setup so that clicking the scroll wheel brings up the Command+Tab application switcher, and clicking the right half of the mouse brings up the secondary click (right click) menu. I also sped up the scrolling and tracking.
Another possibility is for you to create your own scripts to be assigned to the buttons. Some possibilities include Dictionary lookup and search in Spotlight/Quicksilver
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