A number of people use the Plasma desktop and KDE 4 apps over the network using things like VNC. Unfortunately, many of these same people find that Plasma (and styles like Oxygen) often don't look all that hot in their VNC screen.
As with so many "problems" with Plasma, this is not an issue with Plasma (or Oxygen) itself as much as it is with the vnc server. Indeed, the cure is using a decent vncserver such as x11vnc or xf4vnc.
Sadly, krfb doesn't provide such good results. It would be great to see it (and the default vnc servers in Linux desktop distributions in general) get with the program and provide a reasonably modern experience.