I've made this because I'm a regular 15x7 mobile user, and I can't log in to the mobile version of Stack Overflow.
I don't see any log in buttons: log in with Facebook, log in with Google, log in with Yahoo, etc. Except login with open ID
Once I spent 5 hours searching for a solution to this problem. At last, I found that it's just that Stack Overflow doesn't show a log in button in mobile version.
So I've just stolen the log in action URL and made a button which is now visible from any mobile browser.
Is that wrong ?