Some time ago, I shared a spreadsheet of cassettes. I've since added the major attributes of Shimano's derailleurs from the last 20 years. If you're frequently mixing and matching like I am, or just into data, maybe this will be useful.
https://goo.gl/fH9kXj
I'm tempted to redo it with Shimano's specification PDFs. They have a whole lot more detail (things like painted vs anodized construction) I don't find terribly relevant, but I'm open to suggestions for ways to expand this.