MailChimp is a widely used Mailng List delivery and support service.
http://www.mailchimp.com
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Get access to data on 3,650,009 websites that are MailChimp Customers. We know of 1,470,861 live websites using MailChimp and an additional 2,179,148 sites that used MailChimp historically and 865,816 websites in the United States.
Get a list of 3,650,009 websites using MailChimp which includes location information, hosting data, contact details, 1,470,861 currently live websites and an additional 1,052,117 domains that redirect to sites in this list. 2,179,148 sites that used this technology previously and 865,816 websites in the United States currently using MailChimp.