if you prefer to have no search provider in Chrome, go into Wrench -> Options -> Basics -> Manage search engines. add a new search engine with any name and any keyword, then set the URL to "%s". it assumes
http://, because if you aren't explicitly entering the protocol as well then you definitely mean
http://, and if you are including the protocol then that bypasses the search handling anyway.
after mousing over the URL and clicking "Make default" you're done. the default google search doesn't bother me, but some people prefer the explicit separation of URLs and search queries.
if you want to do a search or an I'm Feeling Lucky query, just go back to those same search options and add single character keywords for them.
Keyword: .
URL: http://www.google.com/search?hl=en&source=hp&btnI=I%...
then ". wiki tesla" does what you described without requiring a second input field. if you do more of those types of queries than regular searches, you could make it the default so it doesn't require the leading keyword.
once a few good keyword characters are setup to speed up your common searches like dictionary/wiki article lookups, hn, reddit, etc the lack of a dedicated search field becomes a feature.
