A lot of filmmakers these days try to get the epic film look of the old Cinemascope days. Those are the films that were shot with anamorphic lenses – lenses which allowed to get an extra wide aspect ratio on the standard 35mm motion picture film stock.
As a byproduct, the anamorphic lenses also created artifacts, due to the extra pieces of glass they contained – artifacts like vertically-stretched highlights/bokeh and horizontal streaks with extra flare reflections.
Now, many years and films later, these “artifacts” are actually something that people have gotten accustomed to and associate with the classic “film look”.
To create such a look, you can use real anamorphic lenses, except that they are very expensive and hard to find. Another way is to use computer effects. The most practical method, though, is to use special lens filters.
You can also get the CineMorph filters on eBay