OpenTTD
OpenTTD, as it’s name implies, is an open-source remake of 1995 game Transport Tycoon Deluxe. Back when I had my first computer, TTD was one of my favourite games. So what was Transport Tycoon all about? Basically, you have to build a transport network, using Trains, Planes, Trucks, Buses, Boats etc and earn as much money as possible, sounds simple...