For all the criticisms that DiP gets, it is still the best formatted online book I've come across. The line number/hover over highlight thing is awesome. The code examples are interesting. The explanations are in-depth without spending 10 pages holding your hand.
I learned quite a few cool Python tricks from DiP and it was the first book that got me excited about programming. I remember reading the chapter on list comprehensions and thinking they were the coolest thing ever (and I still love 'em!). Whether or not all the code is 'pythonic' or uses deprecated methods, it was still worth reading in my mind.