Green lasers can be used for a variety of roles.
They can be used as pointing devices. The ability to form a continuous line in the dark is an added advantage; this has lead to its usage as rescue lights as it can be seen from miles away.
It as been used for laser light shows. It is also used for sky gazing as a person can pinpoint a star by using the green laser.
It can also be used in high-tech weapons for aiming purposes. Because of its high range, Green laser pointers can be equipped in different kinds of weapons. In the movie Alien vs. Predator it was used as a pointing device on some G36k carbines.
The green laser has many advantages. It is fifty times brighter than a red laser because of which it can be seen from miles away, this helps in being rescued if a person is lost.
High and low temperatures do not affect the performance of Green laser pointers so in case a person is lost in a desert, he can still use Green laser pointers to call for help, in other case, even if a person is lost some where in mountains all covered with ice, he can still use it.