Here are eight great things I read this week. 

Stimulus
Lower gas prices are saving Americans billions:

The rout in crude oil prices may mean as much as $75 billion in gasoline savings for U.S. drivers in 2015, according to AAA.

Americans saved $14 billion on the motor fuel last year compared with 2013, Heathrow, Florida-based AAA, the country's largest motoring group, said by email. Pump prices dropped a record 97 consecutive days to a national average of $2.26 a gallon yesterday, the lowest since May 12, 2009.

Efficiency
Even better, a boom in vehicle fuel efficiency means we're using far less gas than before: 

Competition
Wall Street research departments are closing, making it easier for corporate insiders to take advantage to mispricings in their own stock:

From 2000 to 2008, 43 brokerage firms closed their research departments.

But for chief executives and other corporate insiders looking to trade their companies' shares, reduced analyst coverage was a boon, suggests research from Wei Wu, a graduate student at the University of Chicago Booth School of Business. Mr. Wu looked at trading behavior of insiders at companies with five or fewer analysts when, as a result of research-department closures, coverage was reduced. He found that for each analyst a company lost, returns reaped by insiders increased.

Opportunity
When Web pioneer Marc Andreessen graduated college in 1994, he thought he had missed the tech boom:

I just went to college. I did my thing. I came out here in '94, and Silicon Valley was in hibernation. In high school, I actually thought I was going to have to learn Japanese to work in technology. My big feeling was I just missed it, I missed the whole thing. It had happened in the '80s, and I got here too late. But then, I'm maybe the most optimistic person I know. I mean, I'm incredibly optimistic. I'm optimistic arguably to a fault, especially in terms of new ideas. 

Boom and bust
Over the long run, stocks move in long, deep cycles:

Lessons
Josh Brown asked a bunch of people what they learned in 2014. My favorites:

Ben Carlson (A Wealth Of Common Sense): almost everyone in the markets these days tries to portray their opinion as being contrarian, but very few people actually position their portfolios to match those contrarian opinions. Also, be nice to people. Being a jerk is no way to go through life.

Sapna Maheshwari (Buzzfeed Business): the skill set for founding a great brand is extremely different from the skill set required to run a successful publicly traded company -- and investors have finite patience for founder antics.

James Osborne (Bason Asset Management): no matter the market environment, something will happen to make you second-guess your strategy.

Side effects
Electric cars are no solution to pollution:

A battery-powered car recharged with electricity generated by coal-fired power stations, it found, is likely to cause more than three times as many deaths from pollution as a conventional petrol-driven vehicle.

Global investing
Bill Mann writes a great piece on investing overseas:

It has been said that there are four kinds of countries in the world: developed countries, developing countries, Argentina, and Japan.

Argentina just defaulted on its sovereign debt (again). This was such a dramatic event, so systemically destructive, that global markets did ... nothing. If Argentina were a dude, he'd have a rap sheet a mile long and sport an oft-broken nose and a questionable essay tattoo rife with misspellings, like "Tragdey."

Have a great weekend. 

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Contact Morgan Housel at mhousel@fool.com. The Motley Fool has a disclosure policy.