Automatically fills in sensible default conditions when you have filters with your cargo wagons. Makes vanilla style train basing and direct train to assembler builds much less tedious.
Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.
Satisfy your addiction and safely consume glowsticks virtually. Just replaces fish with glowsticks.
Mods introducing new content into the game.
Selectively remove equipment grids from various entities and vehicles (such as locomotives, cargo wagons, etc). Saves some UPS if a mod adds equipment grids but you're not using it.
Small changes concerning balance, gameplay, or graphics.
Have you ever wanted to play Desert Bus except in factorio? Well too bad, I made it anyway.
Mods introducing new content into the game.