Puzzle

In Flock! you control a flying saucer and must drive scared animals to your mothership through obstacles and traps. The game also features a proper campaign for 2-player co-op and a map editor.
Like in Switchball and a couple other "cross-platform" titles, the framerate is capped to 30 fps.

2D puzzler that involves using drops of goo to build bridges and structures to help the goo escape form the world.

Crazy Machines 2 is a contraption builder/puzzle game very similar to good ol' DOS-based The Incredible Machine (1992), although with gorgeous 3D graphics and a sophisticated physics model.

Developped by a handful of talented french students, I-Fluid is a 3D "ball game" in which you play as a water drop. Roll and jump to avoid absorbing or hot surfaces, push smaller objects and make your way through 15 levels where apple slices regenerate your health, mugs are mountains and plants can be used as giant staircases.

Switchball is made by Swedish developer Atomic Elbow, which was released for Microsoft Windows on June 26, 2007. Switchball is an intricate puzzle game set in a stunning 3D world. Control an ever-changing ball along a narrow winding course suspended in midair. Solve your way through challenging levels jam-packed with obstacles, traps and mazes. Morph the marble ball with metal, electric and lighter-than-air properties to more easily get through each area.

Spectraball is an indie game that combines elements of platforming, puzzle solving, addictive game play, and stunning visuals to deliver an experience that sets a new standard for the genre. In December 2012, Spectraball received a major update and is now dubbed Spectraball: Extended Edition.

Armadillo Run is a physics-based puzzle game. You have to build structures with the purpose of getting an armadillo to a certain point in space. There is a selection of building materials, each with different properties, which can be combined to form almost anything. The realistic physics simulation gives you the freedom to solve each level in many different ways.

You can download and buy the game at http://www.armadillorun.com/

Portal is a Source-engine puzzle game. Players use a first-person perspective to explore a three-dimensional environment that is broken up into a series of levels. The only device available to the player is a portal-placement gun that is used to solve the puzzles. Players can place up to two portals that can then transport the player (or anything else) through them.Portal is a puzzle-lite game with an emphasis on faster replays and conditional achievements.

Yohoho! Puzzle Pirates is an addicting 2D MMOPG (MMO Puzzle Game) from Three Rings Designs. The game offers both free game play, and pay options. In addition, it offers International Seas (Servers) and is available for Windows, Mac, and Linux. Finally, the game offers full-screen and window gameplay.