RocketDock - RocketDock is a Mac OS X dock clone.
DockbarX - DockbarX is a standalone dock that groups and launches applications.
Winstep Nexus - The Winstep Nexus Dock is a FREE* professional dock for Windows. With Nexus, your most frequently used applications are only a mouse click away - and Nexus turns working with your computer into a fun and exciting experience.
Gnome-Pie - Gnome-Pie is a circular application launcher for Linux.
ObjectDock - ObjectDock is the most popular animated dock for Windows.
Synapse - Synapse is a semantic launcher written in Vala that you can use to start applications as well as find and access relevant documents and files by making use of the Zeitgeist engine.