Putting "widgets" on Mac desktop
In some versions of Mac OS X it is possible to detach widgets from the Dashboard and leave them on the desktop.

Enable Dashboard Development Mode


Launch Utilities > Terminal.app
Issue the command defaults write com.apple.dashboard devmode YES
Issue the command killall Dock
Quit Terminal.app
Display the Dashboard; using the F12 key
Click and hold on a widget
Hide the Dashboard; using the F12 key
In development mode, the widget remains visible and can now be positioned on the Desktop


These steps were originally for Mac OS X 10.4 but this technique is reported to still work with 10.8, Mountain Lion.