I always post this link when Blender is discussed because it's so impressive. It shows what a single person can achieve in Blender. The visual effects and compositing have been created by Blender expert Ian Hubert. The video shows a (grimy) futuristic city scene. Green screen footage and the final shots created are shown side-by-side:

VFX Breakdown - Dynamo Dream Teaser: https://www.youtube.com/watch?v=FFJ_THGj72U

The full short Dynamo Dream was posted a few months ago by Hubert on his YouTube channel:

Episode 1 : Salad Mug - DYNAMO DREAM: https://www.youtube.com/watch?v=LsGZ_2RuJ2A