How to confuse a telemarketer

I just got a call from some telemarketer trying to sell antivirus.

Me "Hello?"
Telemarketer (in heavy Indian accent) "Hello I am calling about your Windows computer."
Me "Um, OK."
Telemarketer "We have been receiving signal that your Windows computer is infected with a virus which is why your computer has probably been seeming so slow lately..." (continues talking about antivirus for about a minute)
Me "Uh-huh."
(Telemarketer continues rambling for a while.)
Me "Yeah, the thing is, I don't actually use Windows."
Telemarketer "You do not? What do you use?"
Me "I use Linux."
(pause)
Telemarketer "Lee-nox?"
Me "Yeah. It doesn't really get viruses."
(long pause)
Me "So I don't think I'll be needing your services." *click*

I've heard about these kind of scams before, where some shady company calls to tell you your computer is infected with a virus and then sell you some piece of antivirus that is either useless or actively harmful, so luckily I knew what to do. It was pretty funny to throw this clod a curve ball - I could practically hear him thinking "fuuuuck, no-one's ever said that before, what do I do what do I dooooo?"