Just done Gish.
On the first Grey level (can't recall the name or number but I think it was the first one) I found a secret room with a giant grey question mark. The dot at the bottom was a block with a miniaturised picture of some sort on it. You can pick up the block and chuck it around, or stuff it half way underground under the other bit. Anyone know the point or relevance of this? Is one supposed to do something significant here?
It was going to be a warp zone, but was removed before Gish was released. The picture you see is the cover of Bridge Construction Set, and I would have loved a warp zone of that
That's a bit disappointing, I thought that I was onto something interesting there. You'd think that they could have at least stuck another life in there or something!
Oh well, at least I know.