I remember I once read a book (around 2008) about this hacker girl who mysteriously sees how a lot of people die in strange circumstances. The story takes place in a very near future (I hope), when you can be connected to the internet at any time without equipment, cause you have a screen of some kind in your eye (kind of like Google's newest invention). You use your hand to control the device.
She ask for the help of one friend that she only knows on the network, and not in real life. At the end of the novel, turns out this friend is a piece of software (AI).
I remember the name was "Beautiful net" but I cannot find it anywhere online...
I've just remember. The main object of the AI software that helped the girl to delete the virus killing people was a chat-software designed to talk to people but to learn and be more natural.
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The girl went to a congress of some sort, and as soon as she approach the place where it will be, she is logged off of the network (she does not need any equipment, cause all is built-in his brain) and to get connected to the congress network she needs the information that will be given once she is there.
There she knows this guy who ultimately turns to be the one who created the virus killing people.