I really like puzzle games. I've played two that are really addictive and beautifully made, and found another that looks great.AuditoriumAuditorium has a free on line demo. I've played through the levels a few times. The full game hasn't been published yet.The screen has a stream of light particles flowing into it. You have one, or more, buttons that will affect the path of the particles: like one that bends the light stream to the right, or one that pulls it into a vortex. You move the buttons around to steer the stream into boxes that are scattered around the screen. There are many particles in the stream, and by careful placement of the buttons, you can split them into different paths. When you hit the boxes with light particles a new group of instruments join a symphony you hear. The goal is to get all of the instruments playing.Some levels have areas that will change the color of the light particles as they pass. Some of the music boxes are different colors, and you will have to route the light particles through the color changer before you send them it into the box. Try it out, the free online demo will make it very clear. I didn't even look at the directions. It's easy to find your way as you go. I love a game like that.PlayAuditorium.comWorld of GooIn World of Goo, you have to stick living gooey balls together to make lattice and build some kind of structure (tower, bridge, rope, ...) that allows the gooey balls to reach the end of a pipe that sucks them up. The Gooey structures are not stiff. If you don't build your structure carefully it will bend and can collapse under its own weight. It is a 2D game with a comic book style to the graphics. There is also a level designer and an online community where you can share new levels. I haven't experimented with these yet - I'm still working through the levels that came with the game.There is a downloadable demo for both PC and Mac. There is also a WII version for sale.It is drawn and designed beautifully. Totally addictive.2dboy.comCrayon PhysicsI haven't played this yet but it looks really great.The graphics look like they were drawn by a 5 year old with a box of crayons. When you get to a level, it presents a drawn scene with a star and a ball (it's actually an apple. Must be a tribute to Newton) somewhere in it. You have to draw some kind of mechanism, or ramp, or some objects, or... As you are drawing, the objects develop mass.Everything you draw then reacts with gravity. You have to harness the momentum you get from everything dropping to the ground in order to push, throw, drop or guide the ball so it hits the star.Look at the video it is self explanatory. CrayonPhysics.com