One wouldn't be able to see a laser beam from the side. The whole point of laser is that the beam is narrow and condensed. Even if it were like a 3" diameter white-hot steel pipe all the way from the ground to the clouds, you'd be hard pressed to see it from a distance.
Particle beam... there is a reason why particles in LHC are accelerated in vacuum. Otherwise they wouldn't travel very far; air is just too dense. Particle beam weapons are only for spaceships.
[Particle beam]
Charged particles, Mr. Muntz? The death beam....