Public Work is an image search engine that boasts 100,000 “copyright-free” images from institutions like the NYPL, the Met, etc. It’s fast with a relatively simple interface and uses AI to auto-categorize and suggest possibly related images (both visually and content-wise). And it’s fun to just visually click around on related images. On the downside, their sourcing and attribution isn’t great — especially when compared to something like Flickr Commons.