RK Launcher is a free application, similar to the dock

Dock (computing)

The Dock is a prominent feature of the graphical user interface of the Mac OS X operating system. It is used to launch applications and switch between running applications...

 in the Aqua

Aqua (user interface)

Aqua is the GUI and primary visual theme of Apple Inc.'s Mac OS X operating system. It is based around the theme of water, as its name suggests, with droplet-like elements and liberal use of translucency and reflection effects...

GUI

Graphical user interface

In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...

 Or [Mac OS X]. The application has support for themes and can support docklets made for ObjectDock

ObjectDock

ObjectDock is a dock similar to that in the Aqua GUI. It is distributed by Stardock for Windows 2000, 2003, XP, Vista and 7, and comes in Free and Plus versions.- Features :...

 and Y'z Dock. Icons with the file extension .PNG and .ICO can be placed on the dock for shortcuts to applications and documents. The application also mimics the smooth zooming and scrolling effects of the Mac OS X

Mac OS X

Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...

 smooth zooming animations, as well as the effects used when minimizing windows (Aladdin's Lamp Effect).

Download link(s)

Official RK Launcher download for Windows / Mac

Competitors

Other software exists with similar functionality:

• RocketDock
  RocketDock
  RocketDock is an application launcher developed by PolyVector and Skunkie of Punk Labs, working with artist Zachary Denton, for Windows that provides a dock similar to that of the Mac OS X Aqua GUI...
  
  
• ObjectDock
  ObjectDock
  ObjectDock is a dock similar to that in the Aqua GUI. It is distributed by Stardock for Windows 2000, 2003, XP, Vista and 7, and comes in Free and Plus versions.- Features :...
  
  
• Xwindows dock
  Xwindows dock
  XWindows Dock is a clone of the dock in Mac OS X Leopard for Windows. It is freely available under Creative Commons license.-Features:* 2D & 3D Full Skin Customization Design.* Stacks like in Leopard.* Minimize Windows...
  
  
• Avant Window Navigator
  Avant Window Navigator
  Avant Window Navigator is a dock-like bar for Linux, which sits on an edge of a user's screen and tracks open windows. Instead of representing open windows as buttons or segments on a bar, it uses icons to minimize screen space and add visual appeal. Avant Window Navigator was created by Neil J...
  
  
• Y'z Dock
• MobyDock