How pratical are hydrogen fuel cell vechicles?

If a majority of our automobiles were replaced with vehicles which operate on hydrogen powered fuel cells, how could massive amounts of hydrogen be stored safely for refueling? How safe are these cars when the fuel tank ruptures due to collision compared to current gasoline/diesel ones currently in use? How many miles will the vehicles be able to go before refueling?

What about alternate fuel sources for airplanes, trucks, etc?

So all this research that is going into hydrogen fuel cells, hybrid technology, and other alternate energy sources for automobiles, is there any corresponding research for airplanes or trucks, or other such things that require huge amounts of fuel, whether it is jet fuel or diesel fuel?