You can send one way emails using the "Community" module both within the "People" section using "Mass Communication" or in the "Groups" section after creating a group.
1. Select the link icon on the email toolbar
2. Enter the link/URL you would like to use in the bottom box labeled "to what URL should this link go to?"
3. Enter the text you would like to display in the top box labeled "Text to Display"
4. Then select the "Insert Link" button
Now when people click on the words entered under "Text To Display" they will be taken to the link entered under "To What URL Should This Link Go?"