My idiot next door apartment neighbors talked too loud and revealed that they have hacked into my computer. What they said implies that there is a trojan in there. What is the best way to isolate it and have it removed? The facts: - Mac Pro with the most recent 10.4 update. - 2 bootable OS X drives, 1 drive for Windows, 1 drive for data (4 drives total) - NO Bluetooth or wireless devices - Linksys wired router between the DSL modem and CPU which before the incident had no settings changed by me. After the incident, I reset it to factory defaults and changed the admin password. - One of the neighbors accurately described the contents of one of the drives. I have never let them into the apartment. - At one point, one of them said Im on his computer now. I immediately put the machine to sleep, and he said, Oh he must have detected us. - (This freaks me out the most.) With the router/modem unplugged from the machine completely, one of them announced, See? Hes wiping one of his drives. At that moment, I was in fact using Techtool Pro to wipe free space from one of the drives. Ive since put the OS X firewall in Stealth mode, and also turned on logging. Ive watched Activity Monitor and read the logs, but I honestly dont know what Im looking for. Is it possible to remove a trojan, or do I have to start over with a blank drive? Is there a freeware solution for this?