I am trying to create a news letter to go out that will have an image animate when someone hovers over it. they are suppose to find the correct decoration in the email to click to win the prize so when they hover over them 1 will dance. I have it working just fine in basic html for web browsers, the code I am using is a css background so the upper half of the gif is still and the lower half does the moving and it appears when they mouse over it. In emails css backgrounds dont really work for everyone.
<a href="/yourlinkhere" class="cssmouseover" alt="Happy Holidays" ></a>
I work at an e-mail marketing company
Quite a lot of css stuff is not cross e-mail client supported. Have a look at the list shown at this page http://www.campaignmonitor.com/css/
However, background images ARE possible under some conditions (also in Outlook). See this link for more information: http://www.campaignmonitor.com/blog/post/3363/updated-applying-a-background-image-to-html-email
Here is a link to a tool to create code for background images: http://emailbg.net
Hover actions are not possible at all.
Oh.. and Gif files work in almost any e-mail client, except Outlook (2007 and newer). Outlook will only show the first "still"