Built by Stanley? / contents
In Carpet Diem, Stan takes the electron carpet out of Dipper's room and is not seen for the duration of the episode, although he was heard outside. I don't think he got rid of the carpet. I think he took it to his secret lab.
In Gideon Rises, we see futuristic-looking gadgets in the lab. One of the devices seems to be a TV screen, which apparently lets Stan spy on the outside world. We can also see Stan's tattoo lighting up the side of his desk. I believe the trio of Stanford, Stanley, and Old Man McGucket built the lab.
Scaryoke gives us a lot more. It shows a computer, which seems to be searching for something. Considering how slow it was, I think it will take the better part of the second season before it finishes whatever it's doing. My theory is that Stanley was trapped in a distant universe long ago, and the computer is searching for him so Stanford can go on a rescue mission.
Where does it let out?
Stan's lab obviously lets out through the vending machine. But it also has another exit: through the wax museum. Stan shows up in the wax museum room right after Soos discovers it. How else would he have gotten in there?
Another exit presumably leads outside. If, as mentioned above, Stan took the electron carpet to his lab, he would've had to go outside in order to get hit by Dipper's second "Stan shot".
the portal
Dipper said in Gideon Rises that the portal page looked like "a blueprint to build some kind of strange, futuristic superweapon...".
A cryptogram on the maze page in Journal 3 says "The portal when completed will open a gateway to infinite new worlds and herald a new era in mankind's understanding of the universe. Plus, it will probably get girls to start talking to me finally."
In DGTTU - Mailbox, though, the mailbox says that "The era of human enlightenment shall never come to pass." Coincidence? I think not!
