Kernberry's

Super Topology Fixer is a Blender addon that breaks polygon faces with four or more vertices into smaller faces of three or four vertices, working in Edit Mode on selected faces without changing vertex coordinates.

Turbo Charged Custom Vehicle Generator is a Blender add-on that generates a completely customizable vehicle rig. You can set dimensions, horsepower, torque, brakes, steering and drivetrain, then drive the result with the keyboard or record it.