"The idea of replacing spark plugs - a technology that has changed little since their invention 150 years ago - with lasers is not a new one."<p>There's a reason that spark plug technology has not changed in 150 years: it works. The mechanism of a spark plug (and many mechanisms inside of an internal combustion engine) are so simple that they leave little room for mechanical failure.<p>Everyone likes to make the joke about "If Microsoft built cars", but there is some amount of truth to it - automobile engineers value simplicity far more than computer programmers do, as it has a direct effect on reliability. The reliability of a car is far more important than the reliability of an online chat application.<p>Spark plugs as they are now solve the problem, and are cheap. You can buy one for about $5 where I live. That one plug will last years. If by chance it does get dirty and start to fail, I can pull it out and clean it with a wire brush.<p>The "fuel efficiency gain" from a laser plug needs to be substantial to justify the complexity and expense. Leave it to journalists to ignore the practical side of a story and make it all 'science'.