A tractor

An old-fashioned, serious, social-economic simulation game that combines trading, vehicles, mini-games and blowing things up. And tractors.
Your goal is to live a long life and get rich.
The game-world continues on while you're not playing and what you need to do varies depending on what other players are doing and what has been built in the past. Things unfold slowly over the course of many weeks and months - you don't play in a single long session, instead you visit occasionally, collecting money you've earned while you were offline.
To survive you'll need to eat regularly - either by stocking up on food and drink (your character will eat and drink automatically when you're offline) or by visiting a local restaurant. It also helps if you have somewhere to live.
To get rich.. well.. that you have to work out..
The game is free to play, with various minigames and activities open to all. An optional membership provides an extra couple of building slots and reduces skill learn times slightly. (More importantly it helps fund continued development of the game!)