Here's a tip from Tony at TopFreeware.net. He likes to play games occasionally, and this is a good one. I saw a review of the PC version of this game and I was impressed with the unique ideas involved.
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Over 40 challenging, portals thinking levels, which features almost every feature the real game does, in 2d - energy balls, cubes, turrets and even the famous crusher from the trailer. The game also includes a console to mess around with after finishing the game.
Even cooler, there is the freeware predecessor of Portal called Nabacular Drop. Check it out and let us know what you think of it. Below is a video showing some of the mind-bending features.
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