Cheat-bumping this, because Episode Seven has come to the States. (Canadians can watch it at adultswim.com - you'll be better off in the long run for it, no pesky "if-you-don't-want-to-be-spoiled-what-are-you-doing-on-the-Internet" moments.)
Casual perusal of Death Note forums indicates that this is the episode that made more L supporters than any other. It was Episode Five that made an L supporter of me - the subway scene, that is - but this one is just... Go ahead and watch it, if you haven't already. I'll wait.
Clarification for old-timers, also known as a big, fat spoiler:
Do what you will; but I will hinder it if I may.
-- Eowyn of the Mark