I don't approve of people using trojans to attack people, but I would say that if you want a trojan that won't be detected by antivirus, the best way to go about it is to write your own. That way the trojan is guaranteed to be younger than the defences against it, at least for a while, and will probably slip through any checks until someone finds it and informs the AV people.
More importantly, though, if you're able to program well enough to write a decent trojan, the chances are that actually using it in a hostile way will lose much of its fascination and you won't want to make trouble for people any more. Then you might well start writing good, useful software and making a useful contribution to the online community.
- Freon
