The recent post (http://lesswrong.com/lw/5xx/overcoming_suffering_emotional_acceptance) by Kaj_Sotala is very reminiscent of Buddhism to me. Since no one has commented with similar sentiments, and since I get the impression Buddhism is not a common topic of discussion here, I thought I'd make a quick article for the curious. I'm not exactly a Buddhist myself, but I have a good few books about the topic and have experienced mild success with meditation.
Buddhism is one of the few religious belief systems not entirely repellent to me, for a couple of reasons. For one, Buddhism - or some traditions thereof, including the "original" (Theravada), I believe - encourages adherents to be skeptical. The emphasis is not on faith, gods, or symbolism, but rather on actual practice and experience: in other words, on obtaining evidence. You can see for yourself whether or not the system works, because the reward is not in another life. It is the cessation of suffering in this one.
For two, that emphasis on the problem of suffering seems very reasonable to me. Buddhism holds that the problem with this world is suffering, and that suffering can be alleviated by methods somewhat similar to the ones in Kaj_Sotala's post. (The choice of the word "mindfulness" - was that a coincidence, or a reference to the Buddhist concept of the same name?) The idea is that suffering results from unfulfilled desires, themselves a product of an uncontrolled mind. You become upset when the world is This Way, but you want it to be That Way; and even if you try to accept the world-as-it-is, your brain is rebellious. Unpleasant feelings arise, unbidden and unwelcome.
The solution, according to Buddhism, is meditation. There are many different types of meditation, both in technique and in topic meditated upon, but I won't go into them here. Meditation appears to be physically healthy just on its own; a quick Google search on "meditation brain" will bring up hundreds of articles about how it affects the thinking organ. However, the main goals of Buddhist meditation are a.) attaining control over your own mind (i.e., learning to separate sense impressions from emotions and values, so that harsh words or even blows cause no corresponding mental disturbance), and b.) attaining insight into Buddhist thought about subjects such as love, impermanence, mindfulness, or skillfulness.
Buddhist thought on some subjects (see next-to-final paragraph) I can leave, but mindfulness and skillfulness seem appropriate to LessWrong. As I understand it, the idea behind mindfulness is simply to be aware of what you're doing, rather than going through the motions - and to be aware of, and fix, cognitive biases. For beliefs and mental processes, failing to hit the "Explain" button (to steal from Mr. Yudkowsky) could be considered un-mindful. Things you don't think about are things you could be getting wrong. Skillfulness is related; it's not about skill at some particular task - it's about maximizing utility, to put it simply. The goal is no wasted or mistaken actions. Your actions should not result in unintended consequences, and your intended consequences should never fail to advance your goals in some way. Rationality is thus a very big part of Buddhism, since it is necessary to be rational to be mindful and skillful!
**One important note:** Buddhism has many traditions, and many, many different beliefs. A great deal of it is about as credible as any other religion. For instance, Buddhism holds that there is no "self", ultimately; however, it also holds that people are reincarnated... so what is it that is being reincarnated? I'm sure there is an apology for this somewhere, but the only explanation I've read made less sense than the question. Karma is also a silly idea, in my opinion. I've picked and chosen regarding Buddhist beliefs, and I'm no expert, so if it turns out what I've written isn't orthodox - well, I've warned you!
That's about all I have to say on the subject. Buddhist methods for overcoming suffering have served me well; it is from Buddhism that I first learned to fight depression over things I can do nothing about, and that regret is only useful insofar as it can inspire you to change, and that there is no excuse for being unskillful and unmindful even in the smallest task. I hope this post has served to impart some knowledge, and/or satisfy (or impart!) some curiosity.