fbxkb is X11 keyboard switcher, which provides visual information about current keyboard. It shows a flag of current keyboard in a systray area and allows you to switch to another one.
fbxkb requires NETWM (www.freedesktop.org) compliant window manager. It's written in C and uses the GTK+-2.4 library only (no GNOME is needed).
Most updated info about fbxkb can be found on its home page: http://fbxkb.sf.net/
- fbxkb hasn't options. It just works.