Wi-Fi signal monitor

It's the fact that Flash is designed to be secure from it being used to do damage at a system level. If web programs had such permission, the world would already have been hacked long ago, and we'd all be ruled by the first group of geeks that decided to do it :) The capablities Flash DOES have in this situation are as follows:

The Flash program can be run from a c/c++ (possibly Java, I'm not sure if Java can run Flash ActiveX inside it, anyone know?) wrapper that has the functions built in to do the system level work, and the ExternalInterface can be used to interact with it. (this is most likely what the Yahoo widgets are doing that you refer to)

OR There can be a seperate program of really any language that is allowed to monitor such things, and you can have a socket connection open between the Flash program and the program that does the dirty work.

Again, Adobe built Flash player to specifically not allow it to do such things by itself, because of security. So another program must do it, and Flash can either be displayed by that program, or communicate with it.

Maikatiputkata is a PERFECT example of "It is better to be thought a fool than to open your mouth and prove it." And his kind does not help those of us who try to make AS3 be understood for what it is (not what it is NOT, a low level system program)