Since sliced bread? Well, I don't know if I'd go quite that far. But Jott.com is pretty awesome if you're a person on the go. And who isn't these days? From their website, "Jott converts your voice into emails, text messages, reminders, lists and appointments."
I use it while I'm driving to send myself reminders of To Do's. I call Jott's toll free number, speak my reminder into the phone, and bam! Jott sends me an email of the reminder. Since my email comes to my crackberry phone, that might seem silly. But I ignore the email on the crackberry and when I get back to the office desktop, there's my reminder waiting for me. This is all waaaaay safer with speed dial and a headset than the old pen and notebook I used to use.
You can also set up Jott to send tweets to Twitter, posts to your blog, or even emails and texts to others. Their motto kinda says it all: Life is busy. Talk to Jott. Get Simple Back™.