Since we're digressing, chromatic aberration is in no way similar to red/blue shifting or any other form of relativistic doppler effect.
Chromatic aberration occurs when a lens is not able to properly focus all visible wavelengths of light to the same point (the camera film or photo sensor). When light travels through a camera lens the following effect happens:
The light enters the prism "in focus". Meaning all of the wavelengths are one beam. However, upon exiting the prism, as you can see, the wavelengths scatter as they all refract at different angles. Higher wavelengths (more purple) refract at a much greater angle than the lower wavelengths (more red)
That's why a camera lens is made of both focusing and correcting lenses. Without a lens to correct the refraction when the photo is taken, chromatic aberration occurs.
Light enters the focusing lens for the purpose of magnifying what you're photographing. However, those same beams of light must then re-refracted through a correcting lens. The spot where the beams of light all converge is the focal point and, as long as all of your lenses are calibrated properly, that point is where you will find either film or the photo sensor.
In terms of the effects artistic usage, I personally have never seen it used so heavily in general sci-fi art. That's not to say that the effect isn't used at all, but generally it is purposefully so subtle as to be almost unnoticeable. It will add a level of photo-realism that you cannot obtain otherwise, but generally when utilizing lens filtering, applying a slight focus blur is more effective than an aberration distortion simply due to the fact that the human brain can easily compute motion blurring, but we aren't able to mentally correct for chromatic aberration. It's one of those things that fall firmly in the uncanny valley. Without it, things seem almost *too* perfect, but too much of it can be distracting. The exception to this would obviously be if the piece was designed with this type of distortion effect in mind.