Saturday Morning Breakfast Cereal is like a more vulgar and direct version of XKCD. I've found both of them informative on moral and philosophical problems.
Nick Bostrom's parliamentary model of ethical decision making: article
Gamification of human incentive structures: article
There seems to be a lot of knowledge that LessWrongers have which is fairly awesome, but not particularly well-covered on Less Wrong.
What other sites do people recommend?
I originally came to LW through HN, and Paul Graham was somewhat influential on my early high school thoughts.
I've poked through these a bit on recommendation from other people, and they seem ridiculously useful.
If you want to be super nice, could you link to some of your favorite posts/articles?