If you're bored by the classic kde taskbar applet, you may want to have a look at plasma-icontasks, Windows users can notice this applet looks very similar to Seven taskbar. Its integration with kde workspace is quite good, it can show the percentage of an operation in dolphin and it lets you control Amarok through play/pause buttons. Also plugins can be used to expand its capabilities.
Other features include opening a new instance of an application by middle-clicking on its
icon, minimizing a group and closing tasks via tooltips (have a look at the project page
The software is actively developed (there's a new release almost every day) and it'll be
integrated in kdeplasma-addons starting from KDE 4.8SC.
Meanwhile I've packaged it for Frugalware, so it's available in -current. Installation is
just easy as typing
pacman-g2 -S plasma-icontasks.