You can use Blender to make footage look like it was shot in 1920, by using particle systems and the compositor. Here is how:

Of course, this tutorial is very extensive, you generally don't need 35 min to achieve this effect, but I wanted to show you different ways to achieve the same thing, so I took a couple of detours. If you are already familiar with parts of the tutorial, just use the guides to jump to different sections.

Download the finished Blendfile here! 

Here is an example of what you can do with the effect, using footage from Tears of Steel: