Some of Leonardo Da Vinci's ideas related to machines, mechanisms and structures here
Some beautiful mechanisms here & here
Disguise of revolute pairs here
Crank and Slotted lever Quick Return Motion mechanism here
Animation of parallel jaw pliers based on Watt's chain here
Animation of walking beam engine here
Animation of crude oil pump here
Some models of beam engine here & here
A mechanism based on Stephenson's chain here
Inversions of 4R kinematic chain (animations after 3:05) here
Grashof double rocker 4-bar linkage here
Animations of cam and follower here & here
Types of gear (Animation) by Basic Engineering here
Gears and simple gear train here
Compund Gear train here and here
Understanding PLANETARY GEAR set ! here
Automatic Transmission, How it works ? here

Theory of Mechanisms and Machines