A simple analog clock.
Show the current state of the battery. On hover show percentage of current. battery left
The new advanced application launcher. It is the standard in kde 4.0. It has many features like search, show recently used applications, favorites,...
Traditional menu (like the one in kde3).
A picture applet. It can show a single picture or a slideshow of pictures. You can drop an image to show an image, or drop a folder to start a slideshow of the images in the folder.
Get the color value of any color on the desktop.