If you haven't heard of Microsoft's new search engine, Bing, you should try it out. It actually works surprisingly well. Unfortunately, the Opera browser does not currently include Bing in its search box, so you have to add it manually. Here's how:

1. Go to the Bing home page at bing.com. Look at the pretty picture and read the fun captions. :) Then right click on the search box and select "Create search."
2. In the Create Search box, you can leave the "Keyword" field blank, or assign it a letter or two to quickly perform a Bing search from the address bar.
3. Click on "Details." Tick the two check boxes that appear: "Use as default search engine" and "Use as speed dial search engine."
4. Click "OK"

And you're set!