http://www.openttd.org/en/aboutOpenTTD is an open source clone of the Microprose game "Transport Tycoon Deluxe", a popular game originally written by Chris Sawyer. It attempts to mimic the original game as closely as possible while extending it with new features.
OpenTTD is modelled after the original Transport Tycoon game by Chris Sawyer and enhances the game experience dramatically. Many features were inspired by TTDPatch while others are original.
Significant enhancements from the original game include for example:
* bigger maps (up to 64 times in size)
* stable multiplayer mode for up to 255 players in 15 companies or as spectators
* dedicated server mode and an in-game console for administration
* new pathfinding algorithms that makes vehicles go where you want them to
* autorail/-road build tool, improved terraforming
* cbrown towns, shiplifts, aqueduct
* larger, non-uniform stations and the ability to join them together
* mammoth and multi-headed trains
* clone, autoreplace and autoupdate vehicles
* possibility to build on slopes and coasts
* advanced/conditional orders, share and copy orders
* longer and higher bridges including new ones, full flexible tracks/roads under bridge
* reworked airport system with many more airports/heliports (i.e. international and metropolitan)
* presignals, semaphores, path based signalling
* support for TTDPatch newgrf features
* drive-through road stops for articulated road vehicles and trams
* multiple trees on one tile
* bribe the town authority
* many configuration settings to tune the game to your liking
* save games with zlib compression for smaller sizes which does not interrupt gameplay
* big support for internationalisation. OpenTTD is already translated into more than 40 languages
* dynamically created town-names in 18 languages and newgrf support
Lots of effort has been put into giving OpenTTD a better usability. These include:
* convert rail tool (to e-rail, monorail, and maglev)
* drag&drop support for almost all tools (demolition, road/rail building/removing, stations, scenario editor...)
* sorting of most lists based on various criteria (vehicle, station, town, industries, etc.)
* mouse wheel support (scroll menus, zoom in/out)
* autoscroll when the mouse is near the edge of the screen/window
* sell whole train by dragging it to the dynamite trashcan
* cost estimation with the 'shift' key
* advanced options configuration window, change settings from within the game
Downloadhttp://www.openttd.org/en/download-testingAll servers must use this version(1.0.0-RC1) in order to be here.
ServersGreen = online,
red = offline
DeSent's server 
Title: DeSent's servar
Version: 1.0.0-RC1
Password: Blockland
Bisjac's server 
Title: ?
Version: 1.0.0-RC1
Password: emily
Tom's server 
Title: TomThePolymer's Blockland
Version: 0.7.5
Password: badspot
Tom, download 1.0.0-RC1