Extension:TitleKey

The TitleKey extension provides a case-insensitive title prefix search. It uses a separate table for the keys, so if it works cleanly it can be deployed without an expensive rebuild of core tables, and dumped when Wikimedia gets a nicer backend through MWSearch extension.

For the average site administrator, the benefit of this extension is that it allows search suggestions (e.g. from Opensearch API) to be case-insensitive.