Dockunit (GitHub: tlovett1/dockunit, License: GPL, npm: dockunit) by Taylor Lovett is a Node command-line tool for running tests in Docker containers. You can define a set of containers for tests to run against, which makes it running tests against multiple environments a lot easier.
This is useful if you maintain open source projects. For example, a blog engine could be tested against Node 0.10.x and 0.12.x, or you could even switch framework versions for Express/Rails/Django/etc.
The author includes examples for PHP, Node, and Python, and it seems like you could hook it up to a CI server easily enough.
Are you still searching for the perfect Express middleware for live reloading your app? Daishi Kato sent in easy-livereload (GitHub: dai-shi/easy-livereload, License: BSD, npm: easy-livereload), a new module that uses LiveReload protocol 7.
If you haven't seen it before, then you might want to check out the LiveReload homepage. It's basically a protocol for updating client-side assets. With Daishi's module, you'll get almost instant updates to client-side assets, but also server restarts as well.