There's going to be a SpaceX launch tonight at 5:37PM ET. It's the second launch of the Falcon 9 v1.1, and the first ever SpaceX launch aiming for delivery of a commercial satellite to geostationary. For reference, their usual launches to the ISS are about 250 miles up, tonight's launch to its geostationary home will be ~22,000 miles (actually going to start even higher than that for it's transfer orbit, 22k will be the satellites final resting place though). This requires a second stage reignition once in orbit, which failed during the only other test launch of this version of the Falcon 9. While it will be launched tonight, the satellite won't reach it's final resting place until December 6th.

This is also their first commercial launch. All of their production missions so far have been for NASA resupply to ISS. Their projected cost of launches is about $30-50 million less than their closest competitors, so if this goes well they could see a swell of commercial launch bookings.

Live casting of the launch will be most likely be found at:

http://www.spacex.com/webcast/