I stumbled over here from Scott Aaronson's blog, which was recommended by a friend. Actually, LessWrong was also recommended, but unfortunately it took a while for me to make it over here.
As far as my descent in to rationality goes, I suppose I've always been curious and skeptical, but I never really gave much direction to my curiosity or my skepticism until the age of 17.
I always had intellectual interests. In 3rd and 4th grade I tought myself algebra. I ceased to pursue mathematics not too long after that due to the disappointment I felt towards the public school system's treatment of mathematics.
After my foray into mathematics, I took a very strong interest in cosmology and astronomy. I still remember being 11 or 12 and first coming to realize that we are composed of highly organized cosmic dust. That was a powerful image to me at that time.
At this point in time I distinctly remember my father returning to the church after his mother and sister had passed away. The first church we went to was supposedly moderate. I was made to attend Sunday school there. I did not fare so well in sunday school. During the second session I attended the subject of evolution was brought up. Now, I had a fascination with prehistoric animals and had several books that explained evolution at a basic level accessible to young adults, so when the teacher challenged evolution and told me that the concept of God was not compatible with it, I told her that she must be wrong about God (this was really an appeal to authority, since I considered anyone who had written a book to be more authoritative than anyone who hadn't). Well, she didn't take that well and sent me to stand in the corner. My parents didn't take well to that (both of them being fairly rational and open to science and my mom not being religious at all, but rather trying to support my dad). And so was borne my first religion-science conflict!
Once I entered high school, my artistic interests came to the foreground and pushed science and mathematics into the background. I developed my skill as a visual artists and as a guitarist. I studied music theory and color theory and played. It was enjoyable work and I took it to the point of obsession. My guitar playing especially, which I would practice for hours every night.
Eventually I decided that I wasn't happy with making art, I wanted to explore something I felt was much deeper and more meaningful. Thus began a period of self reflection and a search for personal meaning. I decided that I wanted to explore my childhood interests, and so I began to study calculus and mechanics during my senior year of high school. It was also at that point that I read Crime and Punishment, Steppenwolfe, The Stranger and Beyond Good and Evil.
Soon I found my way to Kant and Russell. They in turn led me to Frege, Wittgenstein and Quine. My desire to understand myself soon extended to a desire to understand the world around me. Shortly after turning 18, I read Quine's Methods of Logic and was surprised by how natural it felt to me (up until the undecidability part, which threw me through a loop at the time).
By that time, I had begun my major in mathematics. I took every (read every seemingly interesting) course I could to get as broad a view as I could as quickly as possible. This past year (my junior year of college) I took my first few graduate courses. The first was theory of computation. I had no prior experience with the material, everything was new. It was a somewhat transformative experience and I have to say that it was probably the most enjoyable class I've ever taken. I also took a graduate sequence in mathematical logic and learned the famed incompleteness theorems.
I am interested in fighting ignorance in myself and in others and I find that I like the premise of this blog. My current interests include Bayesian Probability (thanks to this site and Eliezer, and to some extent the friend who recommended it to me as well), the game of GO, physics (I am woefully ignorant of real physics, and have decided that I need to read up on it), mathematical logic, Fluid Concepts & Creative Analogies (Hofstadter), cognitive science, music, history and programming. It is not hard to get me interested in something, so the list is much more extensive than that and is highly subject to change.
Well, I feel like I've rambled up a storm here.