Use a new organization-known project that combines many different stakeholders, and departments to incentivice collaboration by openly sharing knowledge and information (just like an organization-based Facebook).
It won't be necessary to install new databases or technology.
The first step is to make most (except HR, and top c-level management ones) folders public (read only) to all employees in the organization. Let it open while doing the project, and beyond.
Radical enough? I think YES! I have experienced it several times over past decades, and surprisingly this is best to pull out human creativity, and enable collaboration across departments.