Web service for account balance queries. Would use something like http get query with username, password and a web service key token to stop brute force attacks etc.
Would return balance (in £), goodybag remaining mins, remaining texts, remaining data and expiry.
I want to integrate my GiffGaff account balance into software on my laptop. Would be handy just to query a web service and get data returned in a consistent format so I can display account balance etc on my laptop's top status bar.