Love this idea for 'built-in' storage. use ikea shelves and molding to make faux built-ins for toy storage. hang curtains in front. This actually makes me wonder if walls in lala'sroom adjacent to window box could be made into built ins.
Bookshelves flanking a window, with the curtains hanging from the ceiling in front of the bookshelf. This picture also incorporates horizontal shelving as a window seat, but can definitely face bookshelves outward (into the room) and omit the window seat.