To add some anecdote, I remember doing a short animation with a Star Wars A-Wing Fighter (the model for which I downloaded, not made myself). I added light sources in the engines for that "glow" effect.

Unfortunately, I messed up some of the geometry in the animation, so while the A-Wing was rolling to one side, the two lights were rolling to the other side ;)

Which I of course only found out after a day or so, as renders were so slow (and this was something the size of a poststamp...)