It’s a sad fact that there are few successful open source games. The fact that Battle for Wesnoth continually gets pulled up as an example of a good open source game is proof of that. Not that there is anything wrong with it, but it’s certainly no instant classic. However, luckily for OpenTTD, there are a couple of exceptions.
The basics of OpenTTD are the same as with every Tycoon game – you start up a business, build it up, make money, build it up some more, and repeat. However, after a while, your company is sufficiently successful enough that you will never have to worry about money again. It is at this point that most tycoon games become boring, and you either start a new game, or stop playing. However, with OpenTTD, the business aspect is a rather small part of the game. The main focus quickly switches to the network: How can I transport more passengers? How can I get more trains through this hub? How can I optimise this junction? These are the type of matters I personally focus on most during gameplay.
There are also many more ways to play than just connecting up more places to your network in single player. Some players focus on making picturesque realistic railroads while others combine together to make super-efficient behemoths capable of transporting absurd amounts of goods and passengers each month, bringing with it equally absurd profits.
The game also has a decent community, mostly centred on the forums and IRC. And since version 1.0.0, it doesn’t need the player to own the original TTD anymore, so anyone can play it. While the game obviously doesn’t offer the same creative scope as Minecraft, there are a great many examples of players developing new in-game techniques. People constantly develop new junctions, new ways to build, and some even manage to recreate electronic components in game.
Installation used to be rather complicated, with the requirement for graphics from the original Transport Tycoon Deluxe, but nowadays it’s an extremely simple process. Just download the installer for Windows, or install using your package manager for Linux. If you’re on Windows, make sure to check the boxes for OpenGFX, OpenSFX and OpenMSX. On linux these may be in the openttd package, or they may be seperate packages, depending on your distro.
If you’re still not convinced, I’ll leave you with this timelapse video of someone playing a game on the smallest setting.