Just recently integrated MailChimp into SideProjects.net and sent out its first newsletter today to over 200 subscribers! It contained a brief note where I explained the point of the newsletter as well as a digest of some of the popular side projects that were posted on the site.
All in all, I'm hoping that this will help maintain user retention and keep users coming back to the site. Some people did unsubscribe which is a bit discouraging, but newsletters can become nuisance so it's understandable :)
If you'd like to subscribe, just register on the site and you'll be added automatically.