Pulsus: a particle-herding Time Waster
Pulsus is one of the best physics games I've played in a while. The concept is simple, but the puzzles are challenging enough to keep things interesting. The way it works is that there is an emitter that is putting out purple, orange, and blue particles equally in all directions. The emitter will continue shooting out particles until the countdown timer gets to zero. Your goal is to herd the particles into the receptacles and fill them before the time expires.
There are two different kinds of receptacles, the grey ones that will accept any color particle, and the color-coded receptacles that will also accept any color particle, but when the wrong color go into them, it decreases the meter. Did that make sense? Maybe it's better to just give the game a go.
Your only tools to control where the particles go are forces, which are small circles that you can place that act on the particles. Grey forces repel all particles, and color-coded forces attract like-colors, and repel all others. You get a limited number of forces to solve each level.
The game's graphics are simple but effective, and the game's audio sets the atmosphere beautifully. Pulsus manages to be a time-based puzzle game that is both stimulating and relaxing in equal measures. It won't take you long to complete the game, but it's still definitely worth your time.