It's that time of year again: Warren Buffett is auctioning off a lunch -- with himself. The eBay auction ends this afternoon. Last year's winning bid hit $2.6 million. As of Friday morning, the top bid was $2.3 million (proceeds go to charity).

Most of us don't have that kind of money. Even if we did, $2 million is a bit steep for a meal, regardless of whom it's with.

But what would you ask Buffett if you had his ear for a few hours? Here are 20 things I'd want to know.

1. You've been extremely open over the years. You give interviews. You write op-eds. Your annual meetings attract tens of thousands. Yet you haven't written a book. Why?

2. It's rumored that you keep around $500 million in a personal portfolio that invests in situations too small for Berkshire Hathaway (NYSE: BRK-B) to touch. How has this portfolio done over the years?

3. Your partner, Charlie Munger, has said that if you remove just a few of Berkshire's top investments, its long-term track record is pretty average. Some have used this to claim that at least part -- maybe most -- of Berkshire's success has been a fluke. Is there any merit to that?

4. A lot of Berkshire's success has relied on the decentralization of subsidiaries. That, in turn, is dependent on your ability to find trustworthy managers. But the David Sokol ordeal shows that this isn't fail-proof. Do you worry that a manager could "slip through the cracks," so to speak, and cause irreparable harm to Berkshire? Also, where does the buck stop at Berkshire?

5. You've said in the past that it's a "virtual certainty" the U.S. will experience a nuclear terrorist attack. Where do you get these odds, and how do similar Armageddon probability calculations influence how you manage Berkshire's portfolio?

6. Is whoever replaces you at Berkshire going to have the same investment approach as you do? Would you ever pick a replacement whose style was fundamentally different from yours, but that you still had confidence in?

7. What five laws or regulations could be removed, revamped, or created to help the American economy?

8. A recent paper from MIT talked about how business change and innovation is happening faster today than ever before. How do you find companies with sustainable business models in a world that changes overnight?

9. Berkshire hasn't altered its shares outstanding count in a meaningful way since you took it over decades ago. It hasn't needed to raise equity capital, rarely has it used stock when making acquisitions, and you personally haven't needed liquidity. If you could go back several decades, do you wish your partnership would have just bought the entire company and kept it private?

10. When you started your investment partnership in 1956, there were no large hedge funds, no high-speed traders, and no readily available platforms to access company information. Did that make stock mispricings more common than today? If so, is it even possible for someone today to replicate the success of your early years ?

11. If you could go back 50 years, what industry do you wish you had added to your circle of competence?

12. What's the biggest misconception about the way you invest? What does the media repeat about you that just makes you want to bang your head on the table?

13. If you were to teach a one-semester class on investing, what would the syllabus look like?

14. What investment paradigms have changed over the years? In other words, what used to be an ironclad rule that no long applies to today's economy?

15. Munger says your greatest talent is that you're a "learning machine" -- that you never stop updating your views. What are the most interesting things you've learned since the financial crisis hit three years ago?

16. You're an unapologetic long-term bull on America. But nothing works in certainties. What do you think is the biggest threat to our economy's long-term success?

17. Besides Ben Graham, Philip Fisher, Charlie Munger, Bill Gates, or anyone in your family, who has had the most influence on your thinking?

18. Bill Gates has said that he wants to be remembered for his philanthropy just as much as his contributions to technology. Do you feel differently, given that you've donated the bulk of your fortune to foundations that aren't associated with your name?

19. Be honest. Have you ever Googled yourself?

20. After his lunch with you a few years ago, Mohnish Pabrai said, "The best things about Buffett have nothing to do with investing, but everything to do with leading a great life." Tell me, how do you live a great life?

What would you ask Buffett? Better yet, how do you think he would answer some of these questions? Sound off below.

Check back every Tuesday and Friday for Morgan Housel's columns on finance and economics.

Fool contributor Morgan Housel owns shares of Berkshire. Follow him on Twitter @TMFHousel. The Motley Fool owns shares of Berkshire Hathaway. Motley Fool newsletter services have recommended buying shares of eBay and Berkshire Hathaway. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.