KXDocker 1.1.4a is more attractive than standard task managers. It displays every application as a single icon on a dock on the bottom border of the screen. It offer nice touches such as parabolic zooming of icons, and if you placed too many icons on your dock, you can unite several in one group and cycle through them with your mouse wheel. Or, why use icons at all? KXDocker can grab actual thumbnails of windows and show them instead of icons if you prefer.
KXDocker can show windows from all the desktops or only from the current one. You can have different sets of icons for each desktop. You can configure the behaviour of KXDocker by right-clicking on its icon in the system tray and choosing the Configurator item.
KXDocker is skinnable: you can choose images for different elements of its user interface in the Configurator, or use themes by launching the Theme Manager from the system tray icon menu. This tool allows you to download, preview, and install new themes from KXDocker's Web site.
KXDocker offers much more power than its counterpart from the Mac world, thanks to its ability to use plugins -- special addons for KXDocker. There are plugins available that show the number of unread messages on your KMail icon, and the album cover for the currently playing song in amaroK. You can mount and unmount filesystems, switch desktops, launch the KDE menu, and track CPU usage. KXDocker's plugins can also substitute for such applets as the clock and desktop switcher.
You can obtain KXDocker from your distribution's standard repository if you use Gentoo, Slackware, or SUSE. Otherwise, get the source of KXDocker and plugins from its download page and follow the compilation instructions.
Work in progress
KXDocker is being actively developed. The author is currently working on porting it to Qt 4. The application is stable, though some features don't work the way you might expect them to.
The most annoying surprise is the unpleasant behavior of KXDocker when there are windows of the same application on two virtual desktops simultaneously: even if you want to see only one icon for the application on each desktop, KXDocker shows them as if you have two windows on each desktop (although with KXDocker I felt like I didn't need virtual desktops anymore).
Also, there is a function to show an icon for each individual window of an application, instead of stacking them all on one icon, but KXDocker behaves strangely when you activate it: it starts cloning icons for every application you launch.
There was an (unimplemented and disabled) option to position the dock on top or side border of the screen before version 1.0. The option to place KXDocker on the top side is there, but when I tried to activating it, the dock was placed in random places of screen. However, despite these remaining glitches, the current version is much improved compared to older ones.
If you want to improve your desktop experience, it is a good time to start using KXDocker!