A couple days ago I came across Google's Image Labeler. Essentially, the Image Labeler is a system to allow users to tag images with keywords, with the goal of providing more accurate image search results. The genius of Google's method is that rather than trying to convince users to give up some of their time to sift through and tag millions of images, they turn it into a game.
By default, this search engine looks for all words in any order. To search for an exact phrase, enclose the phrase in quotes:
"the pencil farm"
The search engine also supports AND, OR, and NOT keywords to specify boolean expressions:
products OR design
games NOT review
