My husband had an old flannel bathrobe which he wore until it was so worn out it was falling apart. So I got him a new robe and took possession of the old one.
There were a few spots where the flannel was still intact and strong. I cut pieces from those areas and sewed them into a pillow, sized to fit a basket that our cat likes to sleep in. Then cut the remainder of the robe up into small bits, which I used to stuff the pillow.
It made for a reasonably soft and fluffy pillow, and Gracie cat signaled her approval of the project by sleeping on it all morning.
Making a pillow is a simple enough process, but next time I make an oval-shaped pillow, I will mark some point on the fabric so it is easier to line up the two pieces!