A couple addendums:
1) If you have a family, your death goes on the "would financially ruin you" list. If anyone needs you, you need life insurance - and term is extremely cheap(I just sold a couple half a million each for $50/mo), so don't use money as an excuse unless you're destitute or extremely ill. To a lesser extent, disability insurance(though it tends to be pricier).
2) You may not want to ever retire, but the human body in old age is a very insistent creature. Plan on retiring. Better to have and not need than need and not have.
Further adding on that: Depending on the legal structure of the retirement fund, it can serve as a replacement for smaller insurances or you can have your children inherit it. Or have donated to charity upon your death.
This is the first post of the 2015 repository rerun, which appears to be a good idea. The motivation for this rerun is that while the 12 repositories (go look them up, they're awesome!) exist and people might look them up, few new comments are posted there. In effect, there might be useful stuff that should go in those repositories, but is never posted due to low expected value and no feedback. With the rerun, attention is shifted to one topic per month. This might allow us to have a lively discussion on the topic at hand and gather new content for the repository.
The first repository to be rerun is the Boring Advice Repository, because of... on a whim.
Enter original motivation (by Qiaochu_Yuan):
The Boring Advice Repository is filled with lots of diverse advice, I've summarized some of it in a comment below.
So what should go here? To go with Qiaochu_Yuan again (adding emphasis):
I don't know if you should post new advice here or in the original repository. Perhaps search the old repository with ctrl+f (when on windows) and if you don't get results, post it here.