Via Physorg.com: "John Fleming of SilverEagles Energy and Tim Maxwell from Texas Tech University, say they have developed a way to make ammonia that is cheap enough so that it could be used as fuel for cars. If their claims turn out to be true, many consumers might consider switching over because ammonia, when burned in an engine, emits nothing but nitrogen and water vapor out the tailpipe. And if that's not enough incentive, they claim they can make the ammonia for just 20 cents a liter (approximately 75 cents a gallon)."
In the comments, Akaryrye writes:
According to http://wiki.xtron…_density and cross-referenced with wikipedia, the energy density of ammonia compared to gasoline is about 1 to 2. Gasoline has 9700 WH/L while ammonia has ~4300 WH/L. Taking this into account, powering vehicles with Anhydrous Ammonia would still cost more than half the current per mile cost to power a vehicle. If this could be made practical, it would be awesome, but as with most things, there are technical difficulties in bringing the tech to a practical application.
Methamphetamine manufacturers would be pretty jazzed though.