Control Game-state from an internet browser.

Would be much appreciated.

EDIT:
Just to make clear what I need:

- Some login form that can be displayed within PA. Might be able to be filled out hidden when the user logs in within PA.
- Possibility to verify the username via the concept that the existing login system uses.
- For steamusers it would be cool if the session token had a long lifetime and can be stored in the localstorage.