I found this wasp on the hall floor of my office building and thought I’d take a closer look. It’s covered with dust but I photographed it pretty much as-is. I think perhaps it is a blue mud wasp (Chalybion californicum) which is a widespread species in North America. It is a beautiful, metallic blue color with hints of green, as well. Since the larvae feed on spiders, most people would consider it a beneficial insect, although spiders in their turn feed on other insects and are beneficial themselves.