I like Amazon.com and I spend a lot of time on the site.
One thing about Amazon.com that annoyed me was that when the site loaded, the search box did not have focus set on it. This means that I have to go and _click_ on the search box. Too much work.
Also, when you type something, there is no trigger to automatically start searching for the the text. UX glitch. Again, annoying.
So, I did what every responsible engineer does when he sees a problem. Fix it.
This Chrome extension sets focus onto the search box as soon as you start typing. A la Google. Yes. Enjoy!