It's 12 months later and Warren Buffett's Berkshire Hathaway is $3 billion richer.

One year ago today, on September 23, 2008, with the financial world still reeling from the collapse of Lehman Brothers just days before, Buffett stunned Wall Street with a massive vote of confidence for Goldman Sachs.

In a late-day news release, Goldman announced a private deal to sell Berkshire $5 billion of perpetual preferred stock. In effect, Berkshire was giving Goldman a massive loan. And you don't loan that kind of money to a firm you think could follow Lehman down the drain.

In that release, Buffett called Goldman "an exceptional institution" with an "unrivaled global franchise, a proven and deep management team and the intellectual and financial capital to continue its track record of outperformance."

The next day, in an interview on CNBC, Buffett said, "The price was right, the terms were right, and the people were right."

Buffett's money, and his endorsement of Goldman, didn't come cheap.