When we were in NYC, we spotted a huge Moleskine notebook at Blick art supplies. I was inspired to make my own. It's 12x18 inches of Canson Mixed Media paper. The notebook is covered in brown craft paper and has a black elastic closure.
This was a tricky book to make. Folding and sewing the signatures was no different than a smaller book, but making the cover proved difficult. The craft paper comes on a roll, and the huge sheets I was using really wanted to curl up. On top of that, it was bigger than my work surface, so it was hanging over the sides which made it difficult to measure, cut, and glue with precision. There were quite a few times where I literally threw the misbehaving paper across the room in frustration.
In the end, I am pleased with the final result and have enough paper to make a second one.