Shutter is a powerful screenshot tool w/ many features, it allows you to capture (a specific selection/windows/menu/tooltip/website...), you can easily edit your captures with shutter built-in editor (add text, arrows, crop, highlight,...) and also share (flickr, imgur, etc)
To install it ...
Everyday, a ton of electronic devices are stolen in the world, and it does not only happen to others, and you should protect your devices. That's why I just tested Prey and I think it's quite a good solution.
As the ...
As you know (or not) the ifconfig command is deprecated since many years now and not developped anymore since 2001, it's still present but for now you should use the ip command which is a part of the iproute2 package, it supports all ...