He doesn't find you, you havn't got it all clean yet.
Don't believe me, disconnect your computer from the internet for a few days. I mean physically unplug the lan cable, turn off the modem, etc.
Then continue to do what you normally do (other than surf the web)
Does it hit again? If so then you just proved it isn't a hacker didn't you.
If it doesn't, then perhaps you've proved the reverse is true.
Wipe it clean and start again, this time before you connect to your external drive, make sure you have Threatfire installed, updated, and running. Threatfire isn't a virus scanner, it just sits and watch's for the kinds of changes virus's make in windows registry, etc, then locks it in a box until you decide what it is.
Hopefully it will keep you from getting reinfected by the stuff on the external drive.