Susan used the OLTEDAL bedside cabinet with castors and BEKVÄM spice racks to make a library trolley for her kid’s books. Perhaps the colours are a bit juvenile for you but the same concept can be adapted.
Unfortunately the OLTEDAL is no longer available, but with some ingenuity this can be recreated with a TROFAST storage unit.
Flip the TROFAST around and add wheels to the new base. Add shelves where you want your books to sit. If you want the shelves to be angled, you won’t be able to use the slots for the shelves. Trim the TROFAST shelves and screw them in from the side, at the angle you want. Do add a lip to the shelf to stop the books from falling off. You can hang the BEKVÄM spice racks to the sides or omit them altogether.