Is it worth reporting that I saw a green laser being pointed at the aircraft as a passenger?
In that case I would definitely report the incidence!  It doesn't have to be done by police, but you can give the airport authority a call, that way you don't have to make too much of a big deal about it, and still informed the ones that need to know. They can then advise pilots and keep their eyes open for it. If there is a attack on the airplanes, it is important that it is being reported before it is too late. If not, then you didn't make a big deal out of it and are not in trouble for wasting time and money. 

So, a call where you could explain what you have seen and give a opinion is your best bet, if they tell you off then hey, you've tried it!