For those of you who aren't lucky enough to have a cellphone capable of running Google Maps for Mobile (which is quite a few nowadays, by the way- point your phone browser at m.google.com), Dadnab is a free service providing transit directions via text message for select areas. Of course, I'm mentioning this because Southern California (including Riverside) is one of those areas.
If you're out and about and need transit directions, send a text message with your origin and destination to firstname.lastname@example.org and you'll soon receive step-by-step transit directions. And yes, you can send a text message to an e-mail address. If your phone doesn't allow this, the Dadnab web site provides workarounds for most major wireless carriers.
Google SMS still doesn't support transit directions, so it's great to see somebody stepping up and providing this service. As I mentioned before, the service itself is free. However, you still pay whatever you'd normally pay for text messaging.