Well, wonder no more.. For now there's this neat little website that lets you send an email, and will track when and where it was opened.
It's free to sign up, and you can send a max of 5 emails a day through it.. (they get sent from your primary email address). Not only will it keep track of the emails you send, but it'll also send you an email notification each time an email is opened or an attachment is downloaded (telling you how many days, hours and minutes since you sent it!!) It'll also tell you the location of the recipient, based on their IP address at the time of opening the email.
I don't email much myself these days, but I like the idea of keeping track of the emails i do send, so if you would like to do the same, just signup and start emailing by clicking the banner below: