A registry of 3rd party plugins, features, etc.
Host or maintain a list of 3rd party ServiceStack extensions, similar to ngmodules.org for AngularJS, the listing capability of npmjs.org, or http://plugins.telerik.com/ for Telerik AppBuilder.
The list needs not be actively curated, but a single source where packages are listed and links to download / source code.
As the user base of ServiceStack grows, people are building more extensions that don't necessarily belong in the core modules, and this type of list would provide a great way of bringing attention to them, outside of hard-to-find NuGet packages.

-
As a general place, I'd be happy with people modifying the public Plugins wiki to add their 3rd party plugins: https://github.com/ServiceStack/ServiceStack/wiki/Plugins
For more specific providers they can also be added on the relevant page, e.g:
- https://github.com/ServiceStack/ServiceStack/wiki/Caching
- https://github.com/ServiceStack/ServiceStack/wiki/Logging
- https://github.com/ServiceStack/ServiceStack/wiki/Authentication-and-authorization