EU flights (including flights by US carriers to/from EU countries) must put you up when you're stranded

Flights by EU carriers and all flights to or from EU countries must put you up and pay for meals when you're stranded. They also must pay you a fee if it's their fault, and they need to reimburse you for cancelled flights.

From TFA:

The rules themselves are fairly simple. When a flight is canceled, regardless of the cause, a passenger can choose to get a refund for the unused portion of the ticket or be rerouted on another flight. If this results in an overnight stay, the airline has to pay for a hotel, meals and transportation between the hotel and the airport, even if the cancellation is due to weather or any other factor outside the airline’s control.

If the cancellation is considered within the airline’s control —such as when the plane has mechanical problems — the carrier must also pay each passenger between 125 and 600 euros, depending on the length of the flight and the delay.

Remember this next time you book a flight. It sounds like you might have to make a fuss, but I suspect they'll give in if make it clear that you'll speak up if they don't follow the law.

Recall also that the EU includes quite a few countries.

This is great if you're a EU carrier. I'm hugely in favor of laws like this in the U.S., but I'm also curious about whether such laws provide an incentive for risky flights when conditions are nasty? (Presumably flights are cancelled due to bad weather conditions by the FAA and its EU counterpart instead of by the carrier, mitigating such incentives?)