David Kestenbaum

Nearly 13 million Americans have gotten, or will soon be getting, rebates from their health insurance companies. This is because of a provision in the Affordable Care Act (aka Obamacare) that's supposed to force insurance companies to run better.

But while the idea of getting a check from your health insurance company may sound great, some economists worry this rule could actually make health insurance more expensive.

First, three stories from Thomas Peterffy's life as a trader:

Story #1:

When Peterffy was a kid growing up in communist Hungary in the 1950s his buddy went to Austria and brought back a pack of Juicy Fruit gum. Peterffy bought the pack, broke the sticks of gum up into little pieces, and sold them at a profit. The principal at his school was not amused. "Where's your communist conscience?" the principal asked.

Not surprisingly, given story #1, Peterffy moved to the U.S. as a young man.

Story #2:

We've been talking a lot lately about what's been dubbed the "LIBOR rate fixing scandal," where some of the biggest banks in the world have been accused of manipulating a key global interest rate.

Last week's Supreme Court ruling on the health care law might have made Roscoe Filburn a little happier.

Filburn was an Ohio dairy farmer who had a beef with the federal government, one he took to the U.S. Supreme Court in 1942. He lost.

I recently had a brief conversation with Ronald Coase.

"I'm 101 at the moment," he told me. "I get older by the minute."

Iceland is a tiny nation in a big financial mess. It's still recovering from the aftermath of the 2008 global economic crisis, which caused a domestic banking collapse.

Its currency, the krona, is also in really bad shape. That's led Icelanders to pose an existential currency question: Should they abandon the krona?

One key problem is size. Iceland has about as many people as Staten Island, so there just aren't that many people on the planet who need to use the krona.

"There are more people using Disney dollars," says Arsaell Valfells, an Icelandic economist.

The streets of Beijing and Shanghai feel like an entrepreneurial free-for-all, full of mom-and-pop stores and street vendors selling snacks and cheap toys.

But when you pull back the curtain, you see a different picture: a country where the government still controls huge swaths of the economy.

When you're in China, there's a good chance you're doing business with the government every time you:

• make a call on your cellphone (the government owns the country's biggest cellphone network)

China's economy sailed through the financial crisis unscathed — at least in the short run.

When the global crisis hit, the country's government-owned banks started lending out lots more money. The money came largely from the savings accounts of ordinary Chinese people. It went largely to finance big construction projects, which helped keep China's economy growing.

In 1978, the farmers in a small Chinese village called Xiaogang gathered in a mud hut to sign a secret contract. They thought it might get them executed. Instead, it wound up transforming China's economy in ways that are still reverberating today.

The contract was so risky — and such a big deal — because it was created at the height of communism in China. Everyone worked on the village's collective farm; there was no personal property.

"Back then, even one straw belonged to the group," says Yen Jingchang, who was a farmer in Xiaogang in 1978. "No one owned anything."