+1 Here too. I'm kinda astonished this hasn't been implemented yet. You should be able to create a unique, read-only, guid-like link to your private repo similar to what you can do with files in OneDrive. This is a no-brainer.
+10000 my organization NEEDS this, we have different teams, support teams, testing teams, and some are outsorced... we don't want them to have access to ALL of the code, only to give us feedback about testing results and Issues about the applications, etc..
+1. Youtube allows publishing a video that is only accessible via link. Not private per se, just "unlisted". I need to share repos with online classmates for peer review, but I don't want my beginner code in a new language to be publicly available.