Follow us on Facebook? Twitter? Check both those site for html code to add to footer.php.
Code would be something like this,
Follow us on us on<a href="http://facebook.com/you"><img src="http://www.OurExcellentAdventures.com/popcorn.gif" alt="facebookicon" width="35" height="35" border="0" /></a> and<a href="http://you.com/twitter"><img src="http://www.OurExcellentAdventures.com/popcorn.gif" alt="twittericon" width="35" height="35" border="0" /></a>
with appropriate icons and links of course.