Google Mobile
How did we all get along before "the Google?" As the repository of all knowledge—or at least the index to all the other repositories—it stands head-and-shoulders above the rest. As long as you're sitting at a computer, you have access to all the collected wisdom of the universe, give or take. If you're not parked in front of your computer, you're out of luck. Or at least you used to be.
Google Mobile is your portal into the Oracle of Google through your phone. Send your query via SMS text message to short code 466453
Google Mobile is a free service, but as they say "regular text messaging rates apply".