Off-topic, but in the context of "best mistake", here is John Ringo's definition of serendipity from The Last Centurion:
We were saved by serendipity. (Which is a term meaning "I fucked up but things came out better than if I hadn't.")
Today's post, My Best and Worst Mistake was originally published on 16 September 2008. A summary (taken from the LW wiki):
When Eliezer went into his death spiral around intelligence, he would up making a lot of mistakes that later became very useful.
Discuss the post here (rather than in the comments to the original post).
This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was My Childhood Death Spiral, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
Sequence reruns are a community-driven effort. You can participate by re-reading the sequence post, discussing it here, posting the next day's sequence reruns post, or summarizing forthcoming articles on the wiki. Go here for more details, or to have meta discussions about the Rerunning the Sequences series.