Object Placement Tool - it's a powerful editor extension that allows you to populate your scenes in minutes using simple mouse click instead of regular drag & drop of prefabs and setting all rotation and scale variations by hand. The core feature of this tool is "Physics Placement Mode". In this mode you can place your objects with the help of physics. You can easily create huge amount of objects dropped onto each other, for example - the big heap of books like that shown in this video-demo.

- Place objects on any surface by mouse click (or place only on selected object/layer); 
- Physics Mode to drop objects onto each other and create big heaps of stuff; 
- Randomize rotation and scale for created objects; 
- Align to Surface feature to align created object's up axis to the surface normal direction; 
- Follow Path feature, place new object depending to previous object direction. Good for fence placing; 
- Brush Mode to create objects by bunches; 
- Group objects in the hierarchy or even combine meshes into a single mesh (works for meshes, that shares one material).