Linux Turn Based Strategy Games
Below are a few screen shots, and a list of games in the Turn Based Strategy section:
 

LGeneral

glChess

Ki11egg

Advanced Strategic Command (ASC) is a turn-based strategy game in the tradition of Battle Isle 2/3. It can be played against the computer or against other human players (either hotseat or by mail).
 
Bantumi is a well-known game (also known as Maya) with an AI.
 
Batalla Naval is a multiplayer networked BattleShip game. It supports multiple players and robots at the same time. Clients are available for GNOME, GTK, XView, ncurses, and Win16. Servers are available for GNOME and ncurses. It has support for GGZ Gaming Zone and IPv6.
 
BigTwo - The objective of the bigtwo project is to provide a Dai-Di (Big Two) game playable on a browser, similar to other card games available on the Internet from sites like games.yahoo.com or zone.com. Dai-Di is a card game popular in several Asian countries, and is a cross between poker and hearts. The code for this project is freely available and is released under the GPL license. Both the client and server are written in Java.
 
Bots 'n' Scouts is an addictive multiplayer game that can be played over the network, too. Robots make a race through an empty factory, but they need to be programmed for an entire turn in advance, so they don't always end up where the player wanted.
 
CCB-Dopewars is a Java Swing implementation of John E Dell's old game of narcotics commerce. The aim is to make large sums of money by buying and selling drugs over a chosen period of time.
 
Chessd is a project that takes the last open source FICS sources and creates a truly free Internet chess server (ICS). It competes with the Big Three closed-source ICS services (chess.net, freechess.org, and the ICC).
 
Crimson Fields is a tactical war game in the tradition of Battle Isle. Two players command a number of units on a map of hexagons, trying to accomplish mission objectives ranging from defending important locations to simply destroying all enemy forces.
 
Dama lets you play Turkish draughts, which is rather different from British draughts.
 
Emperor is a strategy game for up to six players, who try to conquer all of the cities in a given world. Players have to explore the randomly generated map and build different combat units. Players can fight each other as well as the computer.
 
FreeLords is a turn-based strategy game similiar to W*rl*rds. It can be played with friends on one computer or via a network.
 
Generic Empire is a simple turn based multiplayer strategy game, written in java, designed to be played over the internet in client-server fashion. It is a generalization of the commercial game Empire Deluxe for the PC. It consists mainly of a server, a client, a map editor, and a random map generator.
 
glChess is a 3D OpenGL based chess game using a GTK+ interface via GtkGLArea. The three dimensional board completely substitutes a real board, and is somehow more user and eye friendly than a flat 2-D chess program. glChess does not provide its own chess engine but uses well known, reliable engines such as Crafty.
 
GNMM is an implementation of the game "Nine Men's Morris" for the GNOME desktop. It supports playing against the computer with adjustable strength.
 
GNU Backgammon (gnubg) plays and analyzes backgammon games and matches.
 
Gomoku.app is an extended TicTacToe game for GNUstep. You win the game if you are able to put 5 of your pieces in a row, column, or diagonal. You lose if the computer does so before you. You can play the game on boards of different size. The game has 6 different difficulty levels.
 
Gothello is a GTK-based Othello program for one or two players.
 
gtkgo - The goal of the gtkgo project is to make a go game for both Linux and Windows, that has skin support and can load computer scripts that can be made by users, so that different go-computers can 'attack' each other or other users.
 
Internet Checkers and Draughts Server (ICDS) is a checkers server that people can connect to. The program xcheckers is currently the main interface to the server, although other interfaces may be written later to connect to the server. Standard telnet connections are also supported. The server currently supports British (American), Pool, International, and Spanish games.
 
Jaquemate is a turn-based Web chess system that allows users to play as they have time to do so. Users are notified over email when it is their turn. The user moves through a frontend that shows possible moves on mouseover of the pieces, moves the piece, and confirms the move, resubmitting the board to the server once the move is made.
 
JTEG contains a Java client/server for the TEG game. TEG is a pseudo-clone of the board game "Risk", a multi-player networked turn-based strategy game.
 
Ki11egg is a Xiangqi (Chinese chess) program, including an AI engine, a GUI, and an opening database.
 
LGeneral is a turn-based strategy engine heavily inspired by Panzer General. Move your units each turn and attack your enemies in order to capture strategic objectives to win a battle. LGeneral uses the SDL library for graphics and sounds.
 
Merchant Empires is a multiplayer, Web-based game of space exploration and economic competition. It is a game of strategy, role-playing, and diplomacy, based on both Trade Wars and Space Merchant.
 
Mindless Automaton lets you play collectable/trading card games (Magic: the Gathering and possibly others) against other people over a network. The game is simply a virtual tabletop; it does not play against you or enforce the rules.
 
NetHack is a single player dungeon exploration game that runs on a wide variety of computer systems.
 
Overflow is a board game for two players or one player against the computer. Put pieces on the board until critical mass is reached, and watch a chain reaction go off. Although the rules are simple, several different tactical considerations are required in order to play the game well.
 
Pythonchess is a small program for playing chess against the computer and, more importantly, for practicing computer chess programming.
 
Rhino is a GUI Othello/reversi game for the Gnome environment. The goal is to have a game with a strong AI, targeted to experienced players.
 
Scorched Island 3D is a clone of a popular DOS game called Scorched Earth in three dimensions. It is a game where you try to shoot your opponent over the hill with different weapons and such (very similar to Worms too).
 
Space Hulk is a great board game which takes place in the world of Warhammer 40000. It is a two player turn-based game where one player plays the 'Marine', the other player plays the alien called 'Genestealer'. This video game is a complete conversion of the board game with the 2nd edition rules. It features playing over the network, either in real time or asynchronously via email.
 
Super Star Trek is a port of the classic Star Trek game for DOS and Linux with a text-based window interface.
 
Tornado is the clone of a C64 game. The goal of the game is to destroy the opponent's house with certain weather phenomena: rain, snow, hail, lightning, and the tornado.
 
Twixt is turned-based, abstract thinking game. Network play is supported.
 
UFO2000 aka X-COM: Gladiators is a multiplayable remake of microprose's X-COM: UFO Defense using the Allegro game programming library. This program requires the data files from original game.
 
Ultimate Othello is an Othello/Reversi game featuring Aqua-friendly graphics and animations.
 
Ultra Tic Tac Toe is a console-based Tic Tac Toe game that supports a number of features including single-player and two-player games, and board sizes from 3x3 to 6x6. It can be compiled using MPI or pthreads, if available.
 
UNFAIR is a simple strategy game, where you are either attacking or defending a planet. Attacking troops can hide together to become stronger.
 
wxAtaxx is a strategy game based on Ataxx. It was written using the wxWindows cross-platform GUI library which is available for Windows, X11/GTK, and MacOS. You can play against the computer, against another human on the same host, or against a user on a remote host over a TCP/IP connection.
 
xiangqi is a Chinese chess game. You can play network multiplayer games or play against the computer.
 
XScorch is a clone of the classic DOS game "Scorched Earth". The basic goal is to annihilate enemy tanks using overpowered guns. Players can purchase weapons and accessories to defend their tank, and they can attack enemy tanks by adjusting the angle of the tank's turret and the firing power. Xscorch supports gameplay with humans and computer AIs, and network gameplay is in development.