Live Search (MSN Search) has some interesting operators, not available in Google Search. These operators were introduced last year, but not many people heard about them.
* linkfromdomain restricts your search to sites that are linked from a certain domain. If you don't add keywords after this operator, you can find some of the pages / sites linked from all the pages available on that domain.
* linkdomain shows only the pages that link to a page from a certain domain. The link operator from Google shows all the pages that link to the homepage of a site or to a certain page, but you can't see these aggregated results. Linkdomain operator is also available in Yahoo Search.
* contains should be followed by a file extension and is used to restrict the search only to pages that contain links to at least a file that has that extension.
u2 feature:flash [ Yahoo ]
* prefer lets you give more weight to a keyword.
* loc is used to restrict a search to domains from a certain country.
So if you didn't find a reason to try Live Search or Yahoo Search, these operators might be a good reason.