I just found an amazing website that basically constitutes a broad exploration (with much discussion) on the art of "being less wrong".
What's interesting is that I happened upon it because my sister pointed out to me the most interesting Fanfic I've ever read: Harry Potter and the Methods of Rationality.
I don't read fanfic, as a general rule... it's usually just somebody's personal fantasies, and almost never as good as the original fiction.
But this one had me hooked from chapter one. It seems to constitute a kind of course-by-example into the Art of Rationality. No doubt more poignant if you've actually read the original, but fascinating none-the-less. Try it and see for yourself.
If you're not into fanfic at all - then feel free to cut to the chase - skip it and go straight to the Less Wrong wiki.
All this stuff is brought to you by the Singularity Institute which is dedicated to making sure that the predicted technological singularity is Friendly, rather than unfriendly, towards us mere mortals. Less Wrong was created in order to build a community of rationalists that would be able to improve the world in general (including, but not limited to the singularity). The soundbite mission statement being raising the sanity waterline