Different parts of GNOME use different themes.
There are GTK theme, Beryl (or Metacity) theme, icon theme, mouse pointer theme. Also, there is a GTK theme engine concept. And so on. This is perfectly OK but it's hard to find themes that much each other well. When trying to mix different themes it's really hard to make them look good as a whole.
So, the question is about good themes that create a complete feeling of the desktop. Post here themes, that you are using, with screenshot. Or maybe some advice on this.