Potassium (a friend whom I can't describe better than "my trusted friend in science") was sleeping over at my place a few weeks ago. We spent all our time playing Portal 2.
Needless to say, addiction struck. Hard.
I had to attend a local go tournament and draw there, but there weren't many requests and so me and Potassium just sat around and complained to eachother about the lack of Portal 2 in our vincinity (or a computer to play it on, for that matter).
That's when inspiration struck.
And Paper Portal was born.
It's basically a modified version of a paper-and-pencil game we used to play at elementary school (much to the annoyance of our teachers) and it works surprisingly well - provided you've got enough childishness, paper, pencils and imagination at your disposal.
Soon, pencils were flying across the room and we gathered quite a crowd of spectators... That's where I decided I want to share this, added a few doodles and scanned some of the levels we played. I added some of the rules we came up with and play by. Now, get going and give it a try :]
Download for bigger size.
[Edit] some notes on how to play it:
You just take turns with your partner at shooting the pencil in order to move. Walls stop you automatically, so you just mark your standing point where the pencil trajectory line hits a wall. Otherwise, you mark it where the line disappears, and it is the other players' turn. You can shoot portals during your turn.
You can shoot a portal using the ruler to aim, then have to hit it with your pencil trajectory to get through. You can shoot portals only at walls within your line of sight (walls block sight).
We marked the act of crossing portals with tiny arrows on the trajectories. You can shoot more than one portal during the game (though the amount is limited for each player), but it makes the previous of the same color (and player) disappear.
To push a small button, just hit it with your trajectory (it does not stop you though.)
A big button stops you and as long as you stand on it or drop a box on it, it is on.
The turrets work simply too... if your trajectory ends in their line of sight (a triangular shape, to make it more dangerous), the turret kills you and you start over from the elevator.
We played it co-op but raced eachother to the elevator for some competition. You could alternatively count steps (trajectories) the goal being to pass the chamber with as little as possible.
If you have more questions or ideas, please ask/share them in the comments!