my dad's been cycling more as an effort to get more exercise and he recently bought a trainer for it, so like
you prop up your front wheel on something, you take the back wheel completely off and replace it with the trainer. the whole bike now stands up even when it's not moving, and if you pedal it just turns a sensor on the side. but it connects to your computer so you can get stats about the good biking you're doing
and i just saw my dad using this program with a fully rendered 3d world and an avatar on a bike that was copying him, surrounded by stats about his real-world biking. i thought that was kinda neat but i was gonna kinda tease him about it until i saw other bikers on the road, and my dad said "yeah those are other real people using the program"
in fact, he went on to say "the mechanic is disabled right now because i'm in training mode, but otherwise, if i was right behind another person the trainer would lower the resistance a bit to simulate drafting", which is cool anyway but when i asked about "outside of training mode" he also clarified "yeah you can sign up for races and stuff, and it'll put you in different tiers based on your training performance".
it turns out that in addition to like, actually training and exercising and getting better at cycling, he's gaining exp and leveling up, and he's earning in-game currency to spend on new clothes for his avatar
my dad plays a cycling MMO where the controller is a real bicycle