Dashboard is controlled by the Dock (which it fairly common knowledge), but I have noticed that Dashboard takes up a good portion of memory and once it is initialized you can't get that memory back without restarting. That's what I used to think. It's not ground breaking but it is good info to know. Open Activity Monitor, and select the Dock from the processes and hit Quit Process in the top left. The Dock will go away and come right back, the widgets go away but they don't come back until you initialize Dashboard again. Anyone notice that Dashboard becomes a memory hog over time?