Neuroscience Information Framework (NIF)
From the about page:
The Neuroscience Information Framework is a dynamic inventory of Web-based neuroscience resources: data, materials, and tools accessible via any computer connected to the Internet. An initiative of the NIH Blueprint for Neuroscience Research, NIF advances neuroscience research by enabling discovery and access to public research data and tools worldwide through an open source, networked environment.
Example of a subject specific information resource that provides much deeper coverage than possible with Google, for example.
If you aren’t trying to index everything, you can out perform more general search solutions.