It's the level with the mini-fridge :-) Anyway, I found the 2 secret areas around the refridgerator, the one you get to, by climbing the handle-thingy, to the catwalk and jumping across, and the one which is to the top-left of the refridgerator, from where you originally enter the room, to which you get by walking around the fridge (up on top). So where's the 3rd secret area ? (there are 3, 'cause the ending screen says that i found 2 of 3 secret areas).