• !ud Urban Dictionary
• !startrek Star Trek wiki
• !stargate Stargate wiki
• !wayback Wayback Machine
• !tineye Reverse image search
• !bang Check if there are any DuckDuckGo bangs for a particular site
• !itad Is There Any Deal?
• !steam Steam store
• !sp Startpage

You can also use a bang itself, with nothing else before or after it, to just go to the homepage for that website. That can be simpler than typing out the whole URL.

Where do I go to configure that?

We did it, Lemmy!

• CBS, Playboy, CocaCola, ABC, Camel Cigarettes, Windows
• ?, Travelers, Apple, Nike, AT&T, Chrysler
• Warner Brothers, ?, Chase, Intel, Pizza Hut, McDonalds
• Xerox, Adobe, IBM, General Electric, Internet Explorer, Bell Laboratories
• ?, Shell, Adidas, NBC, Pepsi, Compaq

I use Fedora, and I have no idea how to interpret my representation here.