Some browsers allow searching Wikipedia via their URL/Location bar, for example Konqueror, Firefox, and Internet Explorer 7. This is commonly accessed by typing "wp Main Page", but may change according to the browser settings, please check the documentation on whether this feature is in your browser and how to configure it.
It can also easily be added to the URL/Location bar of Opera by right-clicking the Wikipedia search box and selecting Create search.
User:AxelBoldt has created some bookmarklets for Wikipedia searching. You can get them here. That page also explains how to set up a shortcut in Firefox to have Google search all Wikipedias at once.
Finally, if you would like to search for Wikipedia articles in multiple languages, you can try the little-known but very cool multi-lingual Wikipedia search tool (currently disabled).
As you enter text in the search box, it may auto-fill the box. This may be done by Wikipedia or by your browser. By default, Wikipedia will show a list of suggestions based on the entered text. To disable this you must have an account and must be logged in. Go to Special:Preferences, select the Search tab, check the box by 'Disable AJAX suggestions' and click the Save button at the bottom.
When the search suggestions are disabled, your browser may keep a history of searches or may auto-fill— these may be cleared through a browser option:
Internet Explorer 7: Tools → Internet Options → General → Delete → Form Data → Delete Forms → Yes
Firefox 3: Tools → Clear Private Data → Saved Form and Search History → Clear Private Data Now
Safari: Edit → Preferences → AutoFill → Edit → Other Forms; remove Wikipedia from the list
AJAX suggestions may be temporarily disabled if the servers exhibit performance issues.
Check with your lawyer, or just put the site under the GNU FDL. However, Wikipedians try to assume good faith, so minor copyright violations are unlikely to result in a lawsuit.
The database can be downloaded here, but you will need to set up a web server, PHP, MySQL and our wiki software, MediaWiki, to make use of it. A paper or CD version of Wikipedia is currently under discussion at Wikipedia:Pushing To 1.0.
However, several Wikipedians have made various Wikipedia databases available in TomeRaider format for offline reading. See Wikipedia:TomeRaider database for more details.
Cite it as you would any other web page in accordance with the normal citation practice the publication you are submitting the paper to follows. Citing the individual authors is not necessary, but you should at least include the date on which you retrieved the article (and ideally the full timestamp from the history).
Automatically generated citations in several standard styles are available through the "Cite this article" link in the toolbox.
Encyclopedia article pages (mainspace) have white backgrounds, while dynamically generated special pages, talk pages, user pages, and about-Wikipedia pages have light blue backgrounds. This is intended as a visual cue that you're not in the encyclopedia per se.
Because Wikipedia is an all-volunteer project that anyone can edit, errors or omissions can and do creep in. This should be kept in mind when reading; the very nature of Wikipedia means it should not be trusted completely. Articles frequently contain citations of authoritative works where a reader can verify the information found.
