The Cube acts just like the panopticon prison, except, you are sent there when you commit a crime in corpclave.
It's a puzzle like level. Once you are cloned, you go down in to the first room, and then you must walk till you reach the exit.
Every now and then, there is a trap, and it's not obvious as to wat's the right way. Here, however, you have the navigate command, to help
you find and exit, wich is science based, making this a great place to grind it.
Fuck machine + saladooder + ultra-clot. That makes for two traps (monofilament grid and spikes) that do just a little damage, and you don't bleed. If you're lucky and have hyperimmune as well, you stand a good chance of resisting the radiation traps as well.
"I have no science, so I can't navigate?" Yes, you can. Just navigate again each time you get the 'can't make heads or tails' message, and keep doing it until you get 'you are positive you need to go 'direction'. You'll get IP in science. It's possible with no science, it just takes longer, and if you stay in the cube long enough to get a full raw, it gets even easier and the IP start coming faster because you'll get more near misses.
Once it says "You're positive you need to go 'direction'" you should go that way and stop. There might be a trap. You'll still run into traps even on the right track, and you probably won't make it to the next room in time, so just grit your teeth, take it in the face, and heal up by getting horny and wanking. Supposedly, eating your own jizz helps with hunger, too. But always remember to have at least 20 HP or so before moving to a new room, because one or two traps in a row can kill you, at which point you go back to precube and start over again, or if your stars are gone, back to wherever your old cloning facility is.
Most important times to navigate, if you're not doing it to grind science and just want the thousand XP journal, is in the first room out of precube, and any room in the cube with more than two doors. If you come to a room with only one other exit, that's the correct one, but you can still sit in there and navigate your heart out to get the science IP. Also if you need to heal after a trap and end up forgetting which door you came in through (and thus which one to leave through), navigate to find out again.
EDIT: Above all, DON'T WANDER AROUND. It takes a while, and it's tedious, and you'll probably have like 8 rads and 260 hunger by the time you get out if you're lucky, but have someone in your corp ready to grab you and heal you up. If you have phaser, now would be a good time to use it, because when you get out of the cube, there's a train and then some stairs which take you up into the Glass Mesa, which is just great if you're already irradiated, like I was. I stepped up and out and phased right there as soon as I got out, and had Vor come to my phase spot with a trauma kit and a rad detox kit.
Then I went and got something to eat. Get something to eat once you're out of the cube. Tastes good, doesn't it? Tastes like FREEDOM.
That being said, the cube is really fucking hard, so avoid crimes there, before you can mass slaughter everyone one in corpclave.