<a href="mailto:putoalmeida@gmail.com?body=This is the lovely text I'd like to see in the body.">Link</a>
This
?body= part of the link may not work in all browsers, it's not officially standarised. There's also
?subject= and such:
<a href="mailto:putoalmeida@gmail.com?subject=This is my subject&body=This is the lovely text I'd like to see in the body.">Link</a>
If it's for a signature on these forums:
[email=putoalmeida@gmail.com?subject=This is my subject&body=This is the lovely text I'd like to see in the body.]Link[/email]
/ 
