Those boxes were made out of crown molding that was simply ripped at the appropriate places to make the sides. The top was made by ripping crown molding and gluing it back together to form the re curved top.
The cool thing about them is that they look far more complex than they really are.
I happened to make that crown on a W+H Molder but you could certainly do the same thing by starting with some stock molding.
It's interesting to look at a molding profile book, such as the one from Old World Moldings, and imagine what sort of shapes you could saw and re glue them into.
I gave a few away and someone saw one of them and ordered twenty of them to be built as business Christmas gifts (at fifty bucks each - about a thousand bucks for twenty hours work and some cherry that was "too interesting" to go into my usual casegoods projects).
After the run of twenty I decided that was enough.