Battle for Wesnoth is a turn-based strategy game with a fantasy theme. Thanks to the use of SDL, it is available for Windows, GNU/Linux, and OSX, as well as other systems. It has been acclaimed by a number of sources, and is one of the topped ranked projects at The Linux Game Tome (http://www.happypenguin.org) and is ranked in the top 20 projects at http://www.freshmeat.net. It has also had a short feature written about it in The Linux Journal.
Version 0.7 is now available for download from http://www.wesnoth.org. It contains a number of exciting new features and bug fixes.
Lead Developer, Battle for Wesnoth