Furniture designers once sought to hide their joinery. But these days anything goes, with some designers turning the joinery itself into a point of visual interest. A case in point is this 1000L modular storage system:
If you're confused by the joinery, the metal supports have not been fancily machined; what you're looking at are angle irons that sit in dual kerfs cut into the uprights at 45°. It's a little more clear if you look at the raw units prior to lacquering:
Though a bit odd, t's a low-tech and cost-effective solution.
The 1000L is by the strangely-named Italian design firm Abuse Studio. ("Abuse" means the same thing in Italian as it does in English, so I've no idea what message they're trying to convey.)