I just found one way of sending your simple message by using google blog.
You can now send your own Latitude message by creating a custom video for your friend. You can also check out the Google Mobile Blog to learn about some of the other creative ways people are using Google Latitude.
What i know from Google Latitude is that, our email addresses will only use to distribute videos that were sent out and will not be stored or shared.It is just our name will be used in the email sent to your friend.
You can try Google latitude here
