If you use the WordPress Admin Bar you might have noticed the dropdowns are a bit quick on the draw. This plugin enables the jQuery hoverIntent plugin
This plugin slows down the dropdown effect of the WordPress Admin Bar. By default (as of WordPress 3.1.x) the WordPress Admin Bar reacts to any mouseover by dropping down menu items. With this plugin you have to hover over the menu items deliberately in order for them to display.
No configuration necessary -- just enable it and you're good to go.