While the dashboard on the Mac is cool, it takes a lot of memory resources even when the dashboard is not being displayed. If you don't use the dashboard, or you are on a Mac without sufficient memory, you're better off just disabling the dashboard so that more memory is available to your other processes.

To disable the dashboard, open a terminal window and type the following "defaults write com.apple.dashboard mcx-disabled -boolean YES" (without the quotes) and hit Enter. Then type "killall Dock" (again without the quotes) and hit Enter. Your dashboard is now gone.

If you change your mind and want to re-enable the dashboard after disabling it, repeat the steps above but in the first command change the YES to a NO.