Index funds are the best way to invest in the stock market because they offer cheap diversification. Beware, however, sometimes funds labeled as index funds really aren't.
Vanguard? It's all about the XSLV PowerShares S&P SmallCap Low Volatility Portfolio. Check out that performance.
I have often benefited from recommendations for Things I Didn't Know I Wanted.
Given that Less Wrong is a community of unusually intelligent, critical, and self-improvement-focused people, I suspect we can generate a pretty helpful thread of product recommendations — perhaps even a monthly thread of product recommendations.
Rules: