Yoink! has been getting some positive press lately, and it (and a similar iOS app, Gladys) put me in mind of the excellent Fresh by Ironic Software. Fresh, which is macOS only, has a drop zone like Yoink!, but is a touch more complex. It shows recent documents as well as things you’ve put manually in the Cooler, and allows you to tag files. It’s fiddlier than Yoink! in a good way.