10% sounds high, even with the caveat of 'some risk'... how much risk does one have to eat currently to get 10%, exactly?

Speaking of this, does anyone know of any LW posts or other articles about how to make the most of idle capital with some risk?

No, or at least if there is, I haven't seen it. LW doesn't really specialize in finance; but there are so many finance blogs out there that I'd find it hard to believe none were useful, Bayesian, or both useful and Bayesian. (And there's the obvious issue that anyone who really is good enough to do such analyses probably has a finance day job and may not want to give you their analysis for free.)