I’ve been using a voice recorder to take action items in my car for a couple of years now, and since I started messing around writing VoiceXML applications I’ve wanted to create a simple telephone-based reminder service, and the guys at Jott seemed to have done it for me.
The way it works is you set up a Jott account, then you call their phone # (1-866-JOTT-123) and leave yourself a message. They use speech recognition to turn it into text and email it to you. That way when you’re driving down the road and remember something you’re supposed to be doing, you can just call yourself and the todo item will be waiting in your email inbox. I haven’t really used it seriously yet, but I’ll keep you posted.