There is spam campaign about Amazon according to a blog entry at Sophos.

The message reads;
Your transaction has been processed by WorldPay, on behalf of Amazon Inc.
The invoice file is attached to this message.
This is not a tax receipt.
We processed your payment.
Amazon Inc has received your order,
and will inform you about delivery.
Sincerely,
Amazon Team

The attachment is a malware and it is detected as Mal/EncPk-HZ. The author of the article notes that regular shoppers of the online store will recognise that the email does not look the same as those that are sent by the ‘Amazon Team’.

Source: Sophos