I was browing youtube and I found this guy's channel:
https://www.youtube.com/user/thang010146/featured
He has literally hundreds (I think thousands) of videos showing cool CADed mechanisms for gear shiftings, escapements, rack & pinions, linkages, and some miscellaneous stuff on threading on tapers. I'm taking a few hours to browse through his channel, and hopefully I can make some of those models in real life.
Mainly it's tons and tons of gears and levers.
Example:
https://www.youtube.com/watch?v=xs9YzKWG1zs
An innovative gear shifting mechanism for multiple speeds. The like-colored gears turn together on the same hub.