0 A.D. (pronounced "zero ey-dee") is a cross-platform real-time strategy (RTS) game of ancient warfare. It's a historically-based war/economy game that allows players to relive or rewrite the history of ancient civilizations, each depicted at their peak of economic growth and military prowess.
ABC Path Generator is a program and a Perl library that generates layouts of ABC Path based on the input of a random number generator. Giving different seeds to the generator will yield different layouts. ABC Path is a puzzle game in which one should position the letters from "A" to "Y" in a 5*5 grid based on clues. It is featured on brainbashers.com. ABC Path Generator makes use of depth-first-search to find usable final paths, and then assigns the clues for it, also using DFS.
ABC Path Solver is a Perl program and library that automatically solves an ABC Path game while giving the reasoning. ABC Path is a puzzle game in which one should position the letters from "A" to "Y" in a 5*5 grid based on clues. It is featured in brainbashers.com. ABC Path Solver uses a mixture of deduction and solving by trying several branches, which should allow it to solve all initial boards.
Anywhere Board Games (ABG) allows users to play board and card games on the Web in real time on multiple machines (PC, Linux, iPhone, iPad, and Android). ABG runs as a Google+ Hangout App or as a standalone PHP app. Unlike other gaming environments, this one has a peculiar vision: projecting the main board on our table and using laptops or tablets to control players' hands (with other friends joining in remotely). It supports flipping, stacking, rotating, rolling, and shuffling of pieces, so most board and card games are playable.
Armadillo adventure is an adventure game set within a world. It is a codebase, a toolkit for making your own adventures such as King's Quest. The toolkit has an example adventure program that can be easily changed and enlarged by derivation. If you are more interested in dungeoneering games, take a look at the <a href="http://freshmeat.net/projects/tanirs-quest/">Tanir's Quest</a> project.