These are stamped tools that have been designed to, you know, look like stuff. Bones and skeletal motifs seem to be particularly amenable to the treatment; hence "bonewrench." The "fishbone," above, is prototypical, and incorporates 21 distinct wrenches for metric and SAE nuts, 3 flat screwdrivers, a serrated cutting edge, a can opener, a wire breaker, a centerfinding tool, and a lanyard loop hole. Fishbone wrenches are designed to cut from bar stock with minimal waste as shown.
Less mature "skullbone," below, shows a similar concept incorporating all the common metric wrench sizes from 4 to 19 mm. It likewise tesselates to minimize sheet waste as shown.
Generally my bonewrenches are another example of the "delight" principle of design: take something boring and make it unboring. A company like IKEA could run a long way with this idea, selling the wrenches individually or packaging them with furniture as assembly tools. The motif could change every year (perhaps according to the Chinese zodiac?), and the assembly tools themselves might well become collectors' items and provide purchasing incentives for products that included them.