Ever go into the registry of your computer? I do. One time I had to go in there to get Norton out of my computer. The process took two hours, down dark alleys you wouldn't think a computer had.
On such a journey, you learn a lot about how computers...and downloads...operate. And how sneaky little hobos jump on trains and ride them into the next town.
Ever allow Facebook access to your Outlook Express to "look for friends"? Ever go back into the registry and see what's changed? No? Oh.