I’ve started making and selling magnetic bookmarks using my artwork. You can buy them on Etsy here. They work on books of course, but I think these bookmarks are best for planners, notebooks, and pamphlets. Things that aren’t always easy to bookmark without the risk of losing said bookmark.
I’ve opened up some stores so you can buy my art (like the cute watercolor dinos above) on all sorts of different products! Check out my shops on Society6 and Redbubble. Here’s a sample of what’s already available: