Ubiquity is the FireFox extension allowing you to perform tasks including wiki, map, dictionary, etc., while still staying on the same web page (instead of having to jump around pages).
Couple of them are developed as search tools for Oracle -
The first one “oradoc” (I like the most) is developed by Eddie Awad. With preview feature, it is easier to filter out information.
The second one “tahiti” is from Don Seiler at the Pythian group. This one has no preview. Thus upon pressing “Enter”, it will redirect to Oracle’s Tahiti site.
Last one “search-oracle-docs” from Mayuresh Kadu’s blog site is similar to that of Tahiti – no preview but redirected to the OTN’s documentation site.