Here's an interesting service. They provide the ability to send emails and merge in contact info. Nothing too earth shattering (though I like that you can track whether the email is opened).
What I think is cool is the iPhone app.
With this it appears you could have a standard email that you trigger to go out to a prospect --- just by adding them on your iPhone. This might be handy for situations where you are requested to ""send some info"" ... using this you could do it right from your car or on the road.
I'm a big believer in automating as much of this marketing so that you can do it from anywhere....