Earlier today, 71-year-old Ponzi scheme mastermind Bernard Madoff was given the maximum sentence for the 11 criminal counts to which he pleaded guilty: 150 years in jail.

The judge did not mince words: "Here the message must be sent that Mr. Madoff's crimes were extraordinarily evil."

The judge also said that his sentence was symbolic -- to deter any would-be Madoffs from steering down the wrong path. Already, his sentence is substantially more severe than other high-profile fraud cases like WorldCom's Bernie Ebbers (25 years in prison) and Martha Stewart, who served five months in jail on charges stemming from favorably timed sales of ImClone Systems (Nasdaq: IMCL). (Note to future parents: Avoid the name "Bernie.")

Stewart's stock sales saved her about $50,000, according to MSNBC. Madoff stole billions of dollars from investors around the world.

They weren't naive investors, either. According to The Wall Street Journal, victims included asset managers, banks like Spain's Banco Santander (NYSE: STD), and filmmaker Steven Spielberg. Now that the punishment has been meted, though, it's worth asking what us average folks can learn from the Madoff mess.

I put that question to a panel of Motley Fool advisors, analysts, and editors. Here's what they had to say.

Tim Hanson, co-advisor, Global Gains : The first lesson is: Things that are too good to be true probably are. The second and more relevant financial lesson is: Diversification is your friend. One should never have 100% of his or her money tied up in any one thing.

That includes, but is not limited to, one country, one currency, one asset manager, one asset class, one stock, one bank, etc. Immorality, after all, exists everywhere, from famously big companies like Tyco (NYSE: TYC) and Enron on down to tiny Chinese names like Fuwei Films , whose principal shareholders were found guilty in China of misusing state assets. So, seriously, diversify.

Robert Brokamp, advisor, Rule Your Retirement : There are a lot of risks out there -- inflation risk, interest-rate risk, market risk, currency risk, and Risk (the game of world conquest, by Hasbro ).

In light of the Madoff scandal, we will add another to the list: manager risk, the risk that the person handling your money won't do such a good job of it. This isn't just the possibility that your manager is a malefactor; there's also the chance that your manager has lost his touch, or was not much good to begin with. The classic example these days is Legg Mason 's (NYSE: LM) Bill Miller, whose Legg Mason Value Trust mutual fund beat the S&P 500 for 15 years straight before lagging an average 10% annually over the past three years.

Like many risks, the way to mitigate manager risk is diversification. Having more than 10% of your investable assets with one manager is probably too much.

Joe Magyer, Senior Analyst: First, let me just say that there's hardly any punishment that would be too cruel or unusual for Bernie Madoff. Personally, I'd like to see him forced daily to read tales of the ruin he has caused, maybe while being repeatedly kicked by cadre of an unusually cruel oompa-loompas. Continued...