Google is testing out a system for users to place queries through SMS and receive responses the same way. Essentially, you just send a text message to 46645 (GOOGL), and it sends back a reply a few seconds later. They have quite a number of different functions at this point, including business and residential lookups (ala 411) and a dictionary-like word lookup. Currently, all of the services are free (minus whatever your provider charges for sending text messages).
I suppose this may already be common knowledge, but I just heard about it the other night (I was actually watching broadcast TV news for a change). I've played with it a bit, and it seems cool. Its also useful enough to make you wonder why someone hasn't done it previously.
More info here:
www.google.com/googleblog/2004/10/get-411-with-46645.html
I've used it as well. The only thing is, if whatever you are looking for is not registered in Google's local directory, it will not show up. Google local runs almost entirely off of DMOZ, and it takes approximately 6 months to get a site registered into DMOZ once it has been submitted.
All in all it's a fun toy, especially if you can't decide where to go for dinner.
That's assuming the submit works and they actually let you in.
They don't exactly contact you with feedback either.