Pick-and-drop is one of Eiffel Software's exclusive technologies and is provided by EiffelVision. In EiffelStudio it allows you to send data easily from a component of the interface to another.
You can pick every reference to a development object (like a class, a feature or an execution object) with a single click on the right mouse button. Then as you start moving the mouse around - not pressing any of its buttons - a pebble tracks the cursor position, and a line continuously connects the pebble to the object's original position.