This is a panel spacer applet for the plasma panel. It is especially useful if you use the task panel (taskbar) on a separate panel and need something to fill up the remaining space on the main panel so it looks normal.
It's redundant with current KDE version, there's already a spacer provided by the default packages (next to the "Add Widget" button there's an "Add Spacer" button).
Thanks Ahmad. In that case I'll close this.
Status: NEW => RESOLVEDResolution: (none) => INVALID