William Saletan at Slate is writing a series of articles on the history and uses of memory falsification, dealing mainly with Elizabeth Loftus and the ethics of her work. Quote from the latest article:

Loftus didn't flinch at this step. "A therapist isn't supposed to lie to clients," she conceded. "But there's nothing to stop a parent from trying something like [memory modification] with an overweight child or teen." Parents already lied to kids about Santa Claus and the tooth fairy, she observed. To her, it was a no-brainer: "A white lie that might get them to eat broccoli and asparagus vs. a lifetime of obesity and diabetes: Which would you rather have for your kid?"

(This topic has, of course, been done to death around these parts.)