Erebus is a 2D real-time role-playing game. Though in its early stages, it is already playable with three quests. It is a classic point-n-click style RPG, with dungeons to explore, enemies to fight, NPCs to talk to, sub-quests to complete, scenery to interact with, weapons, treasure, and other items to find.
FMG is a futuristic war game based on full metal planet (an 'old' board game) and playable in a Web browser. Land your spaceship on Full Metal Planet, pick up ore, destroy or capture the enemy expensive hardware, and if you can, capture their own freighter with a hold full to bursting. Each game is independent. Although it is playable in English, not everything in the guide is translated yet.
Windys is an action arcade game in a deliberately retro style, featuring ASCII graphics and simulated PC speaker beeps. After a particularly strenuous day at work, you return to your own personal refuge in the form of the Windys fast food restaurant. Not all is as it seems, however, as a new and unconventional manager has taken control, bringing with him an army of undead zombies.
Quabro is an arcade game in which the goal is to destroy colored blocks with a ball using four paddles on each side of the screen to steer the ball and keep it on the field. It is inspired by Breakout and Arkanoid, as well as several of clones created later. It is written in Python using the Pygame library.
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.
Five Hundred is a card game for four players similar to Euchre or Bridge, especially popular in Australia and New Zealand. The wikipedia page has a comprehensive description of gameplay. This version is implemented in C++/Qt. It incorporates graphics from the svg-cards project. Computer players are scriptable in Lua.