MailChimp is a widely used Mailng List delivery and support service.
http://www.mailchimp.com
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Get access to data on 3,199,816 websites that are MailChimp Customers. We know of 1,071,465 live websites using MailChimp and an additional 2,128,351 sites that used MailChimp historically and 636,311 websites in the United States.
Get a list of 3,199,816 websites using MailChimp which includes location information, hosting data, contact details, 1,071,465 currently live websites and an additional 908,151 domains that redirect to sites in this list. 2,128,351 sites that used this technology previously and 636,311 websites in the United States currently using MailChimp.