detecting collisions between bodies: Points, Lines, Boxes, Polygons (Concave too), Ellipses and Circles. Also RayCasting. All bodies can have offset, rotation, scale, bounding box padding, can be static (non moving) or be trigger bodies (non colliding).
test for collision with a circle and point
A number-hash ready to go for Talk Like A Pirate Day
A Phaser CE plugin that brings sloped tile collision handling to Phaser's Arcade Physics engine
Collision detection optimized 2d datastructure for usage in games
Checks if two circles intersect.
manage stdout and stderr so that they do not collide in the console
Optimized QuadTree made by Sopur
  
Observers that can be used for checking specific changes in objects. This mainly consists of a Transform Observer and a Collision Observer for DOM Elements
JS unique short var names generator without collisions
Simple 2D JavaScript collision detection library
Adds module path to exports names
An Extremely fast and lightweight QuadTree made in C++ for NodeJS