Although there are many apps that let you keep list of things (workflowy, thingist, notational velocity for MAC) it lets you access lists right from search box.

With special syntax (<list name>.<item to add>) you can add items to existing list. Or access existing lists with <list name>. This <list name><dot><item> syntax is optional after first use.

Using it as default search engine is privacy safe and doesn't increase search latency.

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