Great news! We have released a shared source component that implements partial cache clearing model. Make sure to download the tool and read more about it. Since it is Shared Source, make sure you understand the support restrictions, etc. first before deploying the tool to production.
This tool does not substitute the Staging module as it provides cache clearing only, not file upload/download functionality.
For the implementations with frequent publish operations enabled (from workflow or single item publishes) and especially for multisite environments, this will significantly improve the performance of the delivery system and take the load off the SQL Server.
What I love about the tool is that the code is available so if there are specific architectural considerations for your implementation, you can reuse the code and implement the solution that fits your needs.
Kudos to Alexey Romaniuha for the actual implementation.
Enjoy and don’t forget to provide feedback!