Well now I have a name to put to it, not that it matters. I came across an article that talked about exactly what I had experienced. (See my post for Jan 14th).
Twice in the last year programs looking very legitimate, in fact imitating windows security systems, popped up on my screen and informed me I had some nasty viruses on my computer. They gave me the option of getting rid of them by pressing the "ok" button, or ignoring it by pressing the "cancel" button.
I handled this incorrectly both times, and both times I got to a place where they wanted me to send them money in order to fix the problem. If you get that far, you've screwed up. The first time I should have known better, the second time I was tired and just wasn't paying attention. The software & message looked very similar to software I was familiar with, but it was anything but.
If a message pops up, look at it very carefully, make sure it's legitimate. Do not respond "ok" or "cancel", until you're positive - those buttons can be programmed to do anything. If you're not positive you're dealing with your normal anti-virus software, hit the red x in the upper right corner to close the program, or just manually turn off your computer and wait a few minutes. When you're back run a complete scan - if you can. Hopefully that will deal with it. If not, try to figure out how to remove it manually.
These programs look very authentic, they hijack your computer to or greater or lesser degree and won't give it back until you send them money (so they say). Anyone who is criminal enough to highjack my computer is probably not to be trusted with my credit card information, and under no circumstances will they get it. I will (and did) reformat my hard drive and re-install the operating system before I send them money.
Ok, so hopefully I'm ready for the next time.