This final note today, wrapping up our trip to the dark side of retail. Clearly we’ve learned ‘sale’ is the name of the game this year. In stores, online. But how long can the ridiculous discounts possibly last?

David Wyss: Frankly , they could probably do this for quite a while.

David Wyss is an economist at Brown University.

Wyss: They’re still making money on most of these things. Now after Christmas, they’ll start dumping these things and then people will start losing money, but it’s better to lose a little than a lot.

The moral of the story, then, is grab the deals while you can. Which is kind of how retail works, isn’t it?