Google has provide a service call Google Suggest which might answer the question in title of this post, but the answer might disappoint you a lot as it sometimes not what you expected.
Here is another very interesting post/discover on Techdo.com: “This Image Could Decrease Your Faith in the Future of the Human Race“.
What is Google Suggest?
As you type into the search box, Google Suggest guesses what you’re typing and offers suggestions in real time. This is similar to Google’s “Did you mean?” feature that offers alternative spellings for your query after you search, except that it works in real time.