Raskin!

TotalFinder brings tabs to your native Finder and more! Other features include dual-panel mode and showing folders before files.

Path Finder is a standalone Finder replacement that takes the Finder's familiar interface and adds numerous powerful features and interface innovations to help anyone be more productive on Mac OS X. It features:

Adds eye-candy effects to windows (and start menu) like deformations (e.g: jelly windows - that makes moved window wiggle like being made from jelly; or fold - which hides windows by folding up horizontally, and unfolds when showing), physics (e.g.: keep momentum - making window to conserve move momentum; or bounce - that makes windows bounce upon receving focus ) and other SFX (e.g.: pixie dust - which makes moved window to leave a trail of twinkling pixie dust; or close puff - which displays puff cloud below cursor when closing window). »

Mission Control, formerly Exposé, is a feature of the OS X operating system.

WinFlip emulates Windows Vistas "Flip 3D" effect for Windows XP. Using the hotkey of your choice, you can find the window youre looking for in a fast, clean 3D interface.

Real Desktop: The desktop embellishment for your PC! Real Desktop is a 3D animated multi desktop manager and the perfect tool to replace your wallpaper.

The ultimate desktop organizer. DeskPose NXT helps you to find your applications fast, organize your desktop and become more productive.

Sawfish is an extensible window manager using a Lisp-based scripting language. Its policy is very minimal compared to most window managers. Its aim is simply to manage windows in the most flexible and attractive manner possible. All high-level WM functions are implemented in Lisp for future extensibility or redefinition.

TopDesk radically reduces the time you spend switching between tasks by giving you the ability to quickly find the window you want from a thumbnail view.

Magican File is a professional program for Mac OS X that let you search and manage files on your disks.