Here is a column that suggests one way to be like the Oracle of Omaha is to buy the SP100 (OEF).
The SP100 has a bunch of the big names that Buffett seems to favor. The article mentions some of the names, and you can also view them at the OEF link. But these are household names. XOM, AAPL, IBM... Etc.
Many folks like to buy Berkshire Hathaway - BRK-A and BRK-B. But at some point, my guess is that Warren Buffett will retire and no longer run the funds. Maybe the OEF is a way to play Buffett without owning Buffett.
Here is a chart comparing the two since the bull market began two years ago. You can see that there are some volatility differences along the way. MSN Money has the beta of OEF at .96 while BRK-A is .46.
