10,000mph hypersonic scramjets

A scramjet can't go as fast as the space shuttle, but it can beat any jet handily, theoretically accelerating up to Mach 15. Don't be planning that trip from New York to L.A. in 45 minutes just yet, though, because this hypersonic technology has a long way to go before it'll find its way into passenger aircraft.

Source: http://dvice.com/archives/2009/08/10000mph-hypers.php