kNemo (KDE Network Monitor) offers a network monitor similar to the one found 
in Windows.  It displays for every network interface an icon in the systray. 
Tooltips and an info dialog provide further information about the interface. 
Passive popups inform about interface changes.  A traffic plotter is also 
integrated.  

knemo polls the network interface status every second using the ifconfig, 
route, and iwconfig.