VERY nice! My roommate and I made a clubhouse for our rats (she has three, I have four)... but it's nowhere NEAR as awesome as yours! Basically... it's just a few boxes taped together. But we stuffed them with newspaper... which the girls LOVE!
Madeittothemoon, newspaper--great idea. Mine also love shredded paper, they stash it in their hiding spots.
Electicnoise, I'm a paranoid mum myself. All my computer wires are taped up high where the rats can't get to (however, I don't leave them unsupervised in the room) and my router and modem are hidden in a big moving box so the rats can't get to it. Everything else is ratproofed, but they do chew everything, carpet included, so I have to watch out for that.