Portal (Flash version)

Quite a complicated game based on quite a simple idea. You have a gun which fires 'portals' - a yellow one and a blue one. The two portals link to each other - anything that goes in one will come out of the other. Then you throw this portal gun into a game where the aim is to get from the start to the finish of each level, and that's it!
There are hints at the top of each level, telling you how to play, and you should remember things like the speed you go into a portal is the same as the speed you come out of the other end. You can only fire the portals on the white walls, and later on you'll come across lasers, cubes and turrets, which make things even more complicated.
The game is based on a game currently on sale called Portal.