How it works
Each coil is a point mass connected by spring forces. Gravity pulls down, springs pull neighbors together. The result: the bottom of the slinky stays still while the top collapses, then the whole thing walks down.
Controls
• Drag any coil to pull the slinky
• Drop — release from current position
• Stairs — add/remove staircase
• Coils — number of spring segments
• Stiffness — spring constant