MailChimp is a widely used Mailng List delivery and support service.
http://www.mailchimp.com
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Get access to data on 3,407,525 websites that are MailChimp Customers. We know of 1,085,874 live websites using MailChimp and an additional 2,321,651 sites that used MailChimp historically and 623,725 websites in the United States.
Get a list of 3,407,525 websites using MailChimp which includes location information, hosting data, contact details, 1,085,874 currently live websites and an additional 997,528 domains that redirect to sites in this list. 2,321,651 sites that used this technology previously and 623,725 websites in the United States currently using MailChimp.