Via Trello invitation:
PayPal Inc invited you to their board Your Account has been charged $479.93 which will be deducted from your PayPal account within 24 hours. If you did not authorize this charge, please call +1 806 414 5350 . to stop the payment.
Note: As of 10:02 AM CST, a man with an Indian accent called back on the same number informing me that they are PayPal and they have missed my previous calls.