[wlesieutre]

With DuckDuckGo as your default search, you can use "!w" to direct a search to Wikipedia, "!g" to send it to google, "!gi" for google images, "!a" for amazon, "!ais" for archive.is, and a lot of other options.

If you're using search as a shortcut to get to some other service, it can be nice to go straight there instead of sifting through whatever garbage has been SEOed to the top of Google.

[gibspaulding]

Perhaps more relevant to the GP, you can use !r to search reddit and !hn to search HN:)

[wlesieutre]

Those are two examples where I might not do it because the built-in search on reddit and HN are worse at finding things than searching the same site through Google. For wikipedia search though, no reason to put that through Google.