Anonymous selling Posteo email vouchers for XMR
The current stock is limited, but one could get email service for a full year by spending 15 EUR in XMR:
The request for a voucher can be made over livechat (IRC) or by email. A monero wallet address will be send to you and after 10 confirmations (~30 minutes) the voucher will arrive in your PMs or email.
Since the site is an onion and emails can be encrypted with the seller’s GPG key, the process can be conducted privately: Tor + encryption + XMR.