Wikipedia
DragThing
DragThing is a shareware Dock application for Mac OS X. Intended for organization and as an application switcher, DragThing allows for multiple docks with user-specified settings such as color, texture and shape. Dock contents can be organized into tabs and paying the shareware fee enables the user to assign a keyboard shortcut to any dock item.
DragThing has won many awards, and in 2010 MacWorld gave it 4.5 mice, highlighting its utility for users who preferred using the mouse over keyboard-oriented launchers such as LaunchBar or QuickSilver.