Yahoo! Widget Engine (formally known as Konfabulator) is a JavaScript runtime engine for Windows and Mac OS X that lets you run little files called Widgets that can do pretty much whatever you want them to. Widgets can be alarm clocks, calculators, can tell you your WiFi signal strength, will fetch the latest stock quotes for your preferred symbols, and even give your current local weather.

Y'z Dock is a program toolbar, very much like the dock in MacOS X. It is no longer being updated but still has a very large user base.

WindowBlinds is a program that enables users to safely add thousands of new visual styles to Windows to change the look and feel of your computer.

TaskSwitchXP is an advanced task management utility that picks up where the standard Windows Alt+Tab switcher leaves off. It provides the same functionality, and adds visual styles to the dialog and also enhances it by displaying thumbnail preview of the application that will be switched to.

Samurize is the popular advanced system monitoring and desktop enhancement engine for Windows. IT professionals, overclockers, gamers and desktop modders alike use Samurize for system information, weather reports, news headlines and much much more.

RocketDock is a smoothly animated, alpha-blended application launcher that is similar to ObjectDock. RocketDock renders quickly like MobyDock, has the visual sharpness of Y'z Dock, and the stability that neither seem to possess.

Rainlendar is a customizable calendar that displays the current month. It is a very lightweight application that doesn't use much system resources or take much space on your desktop.

ObjectDock is a program that enables users to add a "dock" to their Windows desktop that contains short-cuts, running tasks, and "docklets". It is highly configurable, easy to use, and very useful.

Launchy is a free windows utility designed to help you forget about your start menu, the icons on your desktop, and even your file manager.

If you are not familiar with the Alt-Tab task switcher in Windows, it's a keyboard short-cut (hot-key) to enable fast switching between applications/windows. This feature has been in Windows since Windows 3.0 and is largely unchanged since Windows '95!