After years of Check Engine lights for O2 sensors and things like that, I figured the light was pretty much always indicative of relatively unimportant emissions problems. I pretty much ignored it when the light came on within the first couple days of ownership of my FIAT 500--partially because we didn't have a dealership yet, but also because I'd never had a real problem indicated through it. And I'm relatively knowledgeable about cars, certainly moreso than the average consumer.
When it started flashing is when I really started to worry. Good thing I did, too, since the light was triggered by multiple cylinder misfires. The head gasket was either faulty or improperly installed from the factory.
So, please, give me a multifunction display that, on top of displaying average fuel economy, range until empty, and the current radio station, can save my ass too.