Using Electronic Components To Make A Chain Reaction
You should look at The Cog, the video commercial of Honda, for some ideas.  Aside from the fan and the windshield wipers, there is also a section there where speakers are turned on, and the vibration from the sound causes mechanical movement.

Edit:  Russell McMahon gives a lot of interesting ideas in the comments to the original question.  My main suggestion is to use electronic components that interact directly with mechanical and chemical components:  transducers.  Use these for effects such as motion (rigid as well as fluid), sound, and light.  Since integrated circuits are not allowed, just use simple circuits with discrete transistors and transducers acting as switches.