There are three TLDs I block on my computer completely, and all of them are file extensions - .zip, .md, and .mov.

(Yes, the domain "readme.md" exists. Fortunately, whoever owns it is not using their power for evil and does not have any webserver there... but I'm not risking it.)

.md seems overzealous, no? Do you also block .rs? Would break too much I imagine.