Why does light from a laser end up in a concentrated spot? I've heard from several people that photons will always take the path of least action whilst travelling, so why does laser light projected on a surface appear concentrated to a single spot when observed?
 A: You are probably thinking of Fermat's principle which states that the path which a light ray (photon) will take between any two points is the path of least time.  Fermat's principle is unrelated to the ability to focus light to a point.  The ability to focus light to a point is a property which involves the wave nature of light and is limited by diffraction.  
A laser is able to be focused to a very tight spot for a number of reasons, one of which is that the light produced by a laser is highly monochromatic, i.e. it has a single frequency.  This means that the normal chromatic problems with white light go away.  In addition, the geometry of laser resonators produces light which is very nearly diffraction limited.  This means that the light coming from a laser can easily be focused down to the smallest size possible for a given wavelength.  
A: This has nothing to do with any minimisation principle, be it Fermat's Principle as correctly mentioned by @ChrisMueller, or the principle of least action.
As @Jim said above, laser beams come out collimated, meaning they come out pretty much parallel to each other. The reason for this is because light is produced by stimulated emission in an optical cavity with two parallel mirrors. The fact that the laser light is coherent (meaning that photons have a well defined phase relation between them) also helps in producing these collimated beams. 
This is not completely true, as laser beams are slightly divergent, an effect called... beam divergence! This is shown in the picture below. The narrowest point is called the beam waist:
 
As a consequence, laser beams actually tend to diverge over big distances, but the effect is usually small and you can easily go around this problem by introducing a collimating lens which will concentrate the beams to a spot as shown below:

A: All the light travels in the same direction.  There is a chamber that has 2 mirrors inside of it.  When a ray of light is shot from a wire. the light bounces around and soon you have a very dense ray of light.  Now one of the mirrors isn't fully silvered out which makes it also act like a lens.
                                                                       -Aman
