Attach a 'sticker' label to a vehicle. Through integration, labels can be added to locomotives or cargo-wagons randomly.
Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.
Transportation of the player, be it vehicles or teleporters.
Hmm.
I have added a screenshot: https://assets-mod.factorio.com/assets/8772a8e456923302801ddb59a623ce8c973af6b6.thumb.png