anything that has to do with music... in my case: music sheets
when i was at the sewing retreat a few weeks ago, i started creating "stuff collecting journals".
i take a-4 cardboard and fold it to form a spread with a flap on one side.
the spread is covered with fabric (old shirts), on the top of the flaps here i glued on tinted music sheets.
the pages will also have pockets etc for holding cards, tags...
i embellished them with photos (ebay), tapes, stamps...
on the back of the spreads i will glue on paper (with more pockets to hold stuff), and i will sew the spreads into a fabric cover.