In the post I talked about some niche search engines that you could build IF you indexed previously-offline archives, or focused on one domain (like coding or sewing patterns? I also liked a recent YC app which helps you find the best restaurant for a particular dish).

If you were going to compete with Google, GitHub, and StackOverflow for coders’ go-to resource, I would like an editor where as I was typing, a sidebar showed me potential search results — not an AutoComplete or a Clippy, but a continuous reference where if I set font on a<canvas> element or imported a library, a summary would already be in the sidebar.

For a general search engine, knowing your search interest in advance would be near-impossible. So what to do? Alexa and Siri are probably the closest threats (by being a completely different device + UI).