Constant Contact is an email marketing service that you subscribe to monthly and access over the internet. It designs for you elements to put on your website ike subscription boxes and/or import a list of subscribers/recipients and you can then design and send email newsletters and other marketing. You can then monitor response rates, what people have read and clicked on etc, to a reasonably detailed level. For an 'out of the box' solution you have a lot (certainly enough for me) control over the design of emails, managing mailing lists and preferences and more. If you have reason to send bulk emails this is definitely worth looking at - I use it for a volunteer group's email newsletter and even with our meagre funds it is very economical, and saves me a huge amount of time in manually updating mailing lists and other administrative tasks associated with sending a enwsletter. Customer service is also extremely good - based in the US, so overnight delays to respond with time difference sometimes but worth the wait in my experience.

Approximate cost: $40/month