Wildcard certificate from Comodo.
http://www.positivessl.com/ssl-certificate-positivessl_wildcard.php
SSL Certificates · Wildcard
Get access to data on 12,647,072 websites that are Comodo PositiveSSL Wildcard Customers. We know of 2,000,001 live websites using Comodo PositiveSSL Wildcard and an additional 10,647,071 sites that used Comodo PositiveSSL Wildcard historically and 1,216,176 websites in the United States.
Get a list of 12,647,072 websites using Comodo PositiveSSL Wildcard which includes location information, hosting data, contact details, 2,000,001 currently live websites and 10,647,071 sites that used this technology previously and 1,216,176 websites in the United States currently using Comodo PositiveSSL Wildcard.