Hackerville

I want to play a game that sharpens my understanding of computer security attacks and defenses and helps me to pick the low-hanging fruit with regard to keeping my data secure. Of course, the internet itself is just such a game. But the action variance is too high (too boring until it is too exciting, and not in a good way). I want to play a lower stakes game that teaches me how to play the real game (on defense) as safely as is reasonable.

Why aren't people trying to sell me more software for this purpose? The antivirus companies are there, but they hardly count. I saw a crazy commercial on TV a few weeks ago, I didn't actually feel tempted to buy, but I was pleased that there's at least a market for security for home PCs. I think their deal was they have you go to some web site, and it scans and does whatever. Not sure if/how it differs from antivirus.