Wildcard certificate from Comodo.
http://www.positivessl.com/ssl-certificate-positivessl_wildcard.php
SSL Certificates · Wildcard
Get access to data on 12,623,655 websites that are Comodo PositiveSSL Wildcard Customers. We know of 1,600,387 live websites using Comodo PositiveSSL Wildcard and an additional 11,023,268 sites that used Comodo PositiveSSL Wildcard historically and 689,181 websites in the United States.
Get a list of 12,623,655 websites using Comodo PositiveSSL Wildcard which includes location information, hosting data, contact details, 1,600,387 currently live websites and an additional 416,684 domains that redirect to sites in this list. 11,023,268 sites that used this technology previously and 689,181 websites in the United States currently using Comodo PositiveSSL Wildcard.