The Writing Cushion
How a seat-cushion solved an issue that I had with almost every notebook ever

Depending on notebook, I am usually having the problem that the height of the notebook is causing issues writing on or near the edges of the book. I like to keep things consistent whenever possible, but it's usually on the bottom third where my handwriting deteriorates simply because it's a pain to place the hand somewhere.
During last summer already I noticed in Jose Naranja's blog-post about "Useful tools which can be kept in a Notebook" that he is using a foam-cushion to address this issue.
During a grocery trip it dawned me that the same can easily be achieved with a cheapo portable seat-cushion simply cut to size! (I should have taken an image prior the cutting but a simple search for portable foldable foam seat pad
will most likely yield some useful results.)
A quick cutting later and I came out with this:

What I like is, that this can be easily adjusted to height, depending on page-position in the book, and since the cushion is technically still in one piece, just narrower, it is nicely staying in place and not falling into its parts:

And here one example on a page with less of a gap:

I am using these seat-cushions for about a year now and find them very comfortable and of course lightweight and by this saw an significantly improvement to my handwriting. Also they make choosing a notebook much easier as I don't have to take the height of the edge into consideration when looking for a new notebook.