mogwai reviewed Wyrd Sisters by Terry Pratchett (Discworld (6))
Granny Weatherwax, Nanny Ogg, and Maigrat have fairy godmother-dom thrust upon them.
Wyrd Sisters
4 stars
This one was one of the best ones in the series so far. Nice, self-contained story. Interesting characters with lots of funny plays on stereotypes, combined with references to the real world.