Unknown icons in Menu bar

Hey there.

I used a wifi dongle but now I got an internal network card which is working as airport card.
I had to install a third party app, I already deleted it, but I still have an Icon left in the Menu bar?

Maybe someone has a quick suggestion how to remove it?
Or in general how I find out to which application this icon belongs?
It's not clickable and there's no tooltip...

The icon I'm talking about is the first form the left, the USB dongle with the wifi symbol.

Thank you.

So I found out that when I kill "StatusBar" which belongs to "StatusBarApp.app", the symbol disappears. There is inside a Resource called "WLANUtilityIcon.icns". So I would say I got the bad guy... But it's located in "/System/Library/CoreServices/StatusBarApp.app"
That sound's very official. :-|
So what I'm supposed to do?
Do I have to delete the Icon, the whole StatusBarApp or is this the source but not the failure?
Would be thankful for some advice.

Thanks.