Kagi is a paid alternative to ad-supported search engines like Google and DuckDuckGo. It has recently revised its pricing model, reducing the cost for a plan with unmetered searches from $25 per month to $10.

Kagi boasts the following (and more) features:

• Blocking or boosting specific domains in your search results
• "Lenses", which are individual setting profiles (e.g. region locks, domain whitelists) that can be applied to search queries
• All of the Bangs that DuckDuckGo has (e.g. type "!yt" in front of your query to immediately search on youtube.com)
• Universal Summarizer, which works with any website, PDF document, YouTube video and more

This blog post goes into full details about Kagi's capabilities.