Magazine "Jewish Currents" saw Paypal wreck their payroll process after the memo line on a payment to a contributor included the string "Iran", because the contributor had written a piece on Iran for the New York based publication (archived). Paypal's string matching victim offered the following statement on the problem:

What I value most in a payment service is the ability to make payments. If I can’t do that with PayPal I won’t be using it much longer.