With Dashboard KickStart
(formerly Dashboard Start), you'll always have the Dashboard ready to use the first time you want. Without it you'll have to wait for a complete Dashboard start-up sequence as soon as you are ready use it for a first time, making its quick accessibility rather useless.
This application runs in the background and reacts to the starting or re-starting of the Dock and to waking up from sleep mode. When that happens it initiates the starting of the Dashboard.