XWindows Dock is still in beta, so features like plug-ins aren't exactly there yet (although they have the groundwork for them). XWindows Dock does contain two nice plug-ins -- the stack container (quick navigation through folders) and a Gmail mail checker.
Jack Wallen is an award-winning writer for TechRepublic and Linux.com. He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website getjackd.net.