While it's not at all something you can stick in your PC, SpaceX will be attempting an ambitious first launch of its Falcon Heavy rocket today. SpaceX has an excellent run-down of just what the Falcon Heavy is and what its mission profile for today will comprise, but the short take is that it's a bundle of three Falcon 9-derived boosters strapped together to deliver five million pounds of thrust at lift-off. That combo should make what the company calls "the most powerful operational rocket in the world by a factor of two." That power could potentially be used to lift as much as 141,000 pounds of cargo into orbit. The company is live-streaming the event on YouTube, and we've embedded it below for convenience.
I wasn't initially sure whether the Falcon Heavy would continue SpaceX's reputation for semi-reusable rocketry, but it turns out that all three first-stage components of the rocket could return to Earth if they don't go kaboom during ascent. In fact, SpaceX says that the two "side cores" that make up part of the first stage are already flight-proven. If it lifts off today, the rocket will deliver a dummy payload comprising Elon Musk's own Tesla Roadster into a "precessing Earth-Mars elliptical orbit" around the Sun. As of this writing, the launch is scheduled to take place at 3:45 PM ET (12:45 PM PT). Keep an eye on SpaceX's Twitter for more details as they arrive.