When I ran out of blank ATCs, I grabbed my small art journal/sketch pad; it's 4" x 6".
Once the novelty of the above wore off, I tried my hand at some blackout poetry. If you are interested, look up blackout poetry on Google-- amazing examples. I might make mine into collages or note cards.
My back is worlds better, but still not quite there yet. Thanks for all the good wishes. I appreciate it! Happy Valentine's Day too!!