Just to throw my 2 cents in:

Sub7 is the illegal form of a RAT (Remote Administrative Tool) and nothing more. Some features added such as cached pw recovery and key logging make it seem more like a trojan, which it's not. Sub7 does not send out anything unless the controller of the interface asks it to do so.

Nothing more then a remote controll for you PC (although more usefull to those wishing to cause harm)