Harvard, Stanford, Notre Dame, and MIT have all received permission from the IRS to allow donors to invest in their endowments (WSJ, registration required). By structuring investments as charitable trusts, donors receive a regular distribution until death, and then the money goes to the school.

The returns earned by endowments at schools such as Harvard and Yale are impressive. The Harvard endowment has returned 15.2% per year for the past 10 years, crushing the S&P 500's return of 8.3%. In addition to their strong performance, endowments are diversified across so many different asset classes that they often bear a very low correlation to the stock market. While investing in endowments is often inefficient in terms of taxes, the historically higher returns some have earned has more than made up for it.

If tax rules loosen up and allow endowment investors to keep a greater share of their gains, we could see endowments become a popular vehicle for retirement planning. Instead of watching the Final Four basketball games, investors could keep a close eye on which school is earning the highest returns.

I wonder how much correlation there would be between the prestige of a school and the performance of its endowment. As Warren Buffett has said, "Success in investing doesn't correlate with IQ once you're above the level of 25. Once you have ordinary intelligence, what you need is the temperament to control the urges that get other people into trouble in investing."