T-Mobile USA is launching a new flat-rate European data plan for businesses. For $50 per month, T-Mobile will offer its business customers unlimited data roaming in 28 European countries. Although there are no overage fees, T-Mobile does caveat that only the first 500MB will be "full-speed data." The plan, dubbed "Open Europe," will launch next month. It's not currently clear if business users will be able to activate roaming for short periods as and when they need it, or if there is a minimum contract length on the new plan.