Facebook to start charging per. “Login with Facebook” authentication

So how much would it cost you at “$0.005” per. login?

I was just pondering an idea this morning what would happen if Facebook did announce to charge a minute amount for that service (they have NOT really announced anything of the sort btw.).

Would your company pay? What else could they just start asking money for? What power would you have to oppose their decision?

I suppose you’d need to weigh up how much dominance they have in your logins, and the pain your users would go through “signing up” with one of your homebrew’d custom accounts or switching to a Twitter or Google + (hah!) account.