for a bag for my friend's birthday. My project for tonight. Oh, and check out these monsters!
The binding I used in the book yesterday is, as riverlark suggested, Coptic. This is one of my favourite bindings, so simple and versatile. It can be extended to any length (or at least any length I've tried so far, as long as the thread's strong enough!) without collapsing, and the spine it creates is very flexible, opening to almost 360 degrees. The book below is Coptic bound too, from heavy paper (about 300gsm) and I love the way it curls around in one direction but is solid when held the other way. It reminds me of a snake.
I have got a video of this moving and twirling about, but I've been trying to upload it for nearly an hour now, without success, and my brain is starting to hurt... perhaps another day!