Earlier quoted context omitted.
Try keyword search on Firefox: "a foo" to search on amazon, "g foo" google, "i foo" imdb, "m foo" google maps, "w foo" wikipedia, "u foo" urbandictionary, etc... I have more but they are not public sites.
Chrome automatically recognizes searches on sites, so that you can just type "ama[TAB]" in de URL bar, and it will give you a site-specific search straight in the URL bar (provided that "ama" auto-completes to "amazon.com" for you, naturally). This works for basically every site you've ever visited that has search functionality. It's pretty decent.
Sounds like the two could complement each other, like aliases and completion in a shell.