Vendetta Online is a multi-platform 3D space-combat MMO for Windows, Mac, Linux/32 and Linux/64. The game permits players to interact in a vast online galaxy; fighting, trading, and mining their way to success. A "twitch" type real-time combat model makes true player skill the deciding factor instead of character advancement. Massive capital-ship battles shake the foundations of the major nations at war, while others struggle to push back the encroachment of the AI "Hives". A no-strings free trial is available.
Njam is a full-featured cross-platform Pacman-like game that uses the SDL library. It features single and multiplayer modes (local or network), duel games where players compete against each other to get more points, cooperative games where players cooperate to finish as many levels as they can, and great music and sound effects. It includes customizable level skin, many different levels, and an integrated level editor.
While Performous might be classified as a karaoke program, it is actually much more than that. Instead of just displaying the lyrics, notes are also displayed, and the performance is scored based on how well you actually hit the notes. Unlike in many other games in this genre, you will also see the pitch that you are singing, so you can see what you are doing wrong and easily (well, everything is relative) correct your pitch.