The world is discovering LED lights, and for good reason. They last 25 times as long as regular bulbs, they use a fraction of the power, they don’t get as hot and they’re very rugged. They’re cropping up everywhere: in homes, flashlights, car headlights, flat-panel TV screens, movie lights and Christmas lights.

And now, finally, projectors.

Projectors are amazing these days — the ones in corporate boardrooms, the ones in home theaters and the ones that fulfill both functions. But most still have a regular old light bulb inside. A very, very bright one that gets very, very hot and costs very, very much to replace — maybe $300 or $400. And that’s after about 2,000 hours of use.

If you could replace that hot, expensive bulb with LED lights, you’d use half as much power, so you’d be polluting less. Because it would need less cooling, your projector could be much smaller and lighter.

Above all, you’d never have to replace the bulb. The LED projectors in this roundup are rated at 20,000 hours or more — at least 10 times the life of a regular bulb. That’s long enough for you to watch a different movie every night for 27 years, or the “Lord of the Rings” trilogy twice.