The Shrine

Well, it's not called that, but just like the Kakashi Gaiden a couple of months ago, this one goes into Jiraiya's past and explains how he got his contract with the toads, why he wanders the world, and more general info on how he became who he is. Precursor to the continuation of the current arc where he's found out about Akatsuki's HQ and is going to "investigate". It's quite good (as the entire series has been since the Azuma-Hidan arc started) and well worth the watch.

Also, you find out who Naruto's parents are and how he got his name :-)

Of course, there won't be another ep for a couple of weeks when there'll be another double-ep. Right now I'd rather watch it weekly myself.