Are there any areas of study that you feel are underrepresented here, and would be interesting and useful to lesswrongers?
I feel some topics are getting old (Omega, drama about moderation policy, a newcomer telling us our lack of admiration for his ideas is proof of groupthink, Friendly AI, Cryonics, Epistemic vs. Instrumental Rationality, lamenting how we're a bunch of self-centered nerds, etc. ...), and with a bit of luck, we might have some lurkers that are knowledgeable about interesting areas, and didn't think they could contribute.
Please stick to one topic per comment, so that highly-upvoted topics stand out more clearly.
Data visualisation - making and understanding neat graphs that present data. It's not something analytical nerds like us are usually that good at, but it's a skill worth developing. Just look at all this sexy stuff!
There's some tension between presenting data honestly (see this discussion, which motivated me to write this post), and I think LessWrong can have higher standards than some blogs who just like pretty sexy pictures.
(edit: here's another discussion of the tension between data analysis and neat design)
MATLAB is pretty good at this. Are you interested in a tutorial on [data visualization in] MATLAB, or something else?
If people prefer free software, Octave is, I am told, a good free substitute for MATLAB, although I have no experience with it myself and would be unable to write a post on it.