I was recently speaking to someone into art investment and was comparing it with e-commerce.

According to WikiPedia King Francis I bought the Mona Lisa for 4,000 écus in 1519.

What is that in today’s money? A tricky question but someone’s had a good go of working it out here over at Yahoo Answers.

So let’s say the King paid about $270,000. We don’t currently have a value for the Mona Lisa and as far as I’m aware nobody has taken it to the Antiques Roadshow. Let’s just give it a pretty ridiculous valuation of $1 billion.

On that basis the Mona Lisa returned the King’s investment 3703 times over 497 years. Diet Chef returned our investment 899,999 times over 3 years. Therefore Diet Chef as an investment was 24,304% better than buying the Mona Lisa.

So if you are certain that you can identify the next Leonardo da Vinci then the lesson of history would seem to show that it is not a great financial investment.