Since a mention in HN a couple weeks ago I've been using the DDG extension for Firefox, and love it: even if you're not using DDG as a search engine, it adds very cool insights to Google result pages.
The one area it could be a bit better is for some things that are slightly esoteric or articles that are very new. I just search with "!g" added to the query and get those via redirect (of course, that does negate privacy a bit since results are from Google).