First off, let's get our definitions straight. There's the affluent, the rich and the superrich, and according to a survey by Prince & Associates (courtesy of Wealth Report's Robert Frank), their investment choices are quite different. For example, more than two-thirds of respondents worth between $500,000 and $1 million invest in exchange-traded funds, and more than half of them invest in mutual funds. But once you get to between $5 million and $10 million, just one percent invest in mutual funds and 17 percent in ETFs. As for the superrich ($20 million or more), more than a third like startups - and they want to cut the checks themselves. They also go for hedge funds and private equity.

The reasons for these differences are mainly access and suitability. Investing in start-ups is not as feasible for everyday investors because they don’t have all the information on hot new start-ups that the rich often get, known as “deal flow”. And even if they did, everyday investors wouldn’t be able to risk the necessary capital. Hedge funds and private equity also remain largely the purview of the wealthy, since their minimum investment levels are often in the millions (granted, fund of funds and pensions have made it a little easier for the little guy to get in).