For our save the date cards, we decided to create postcards with scratch-offs. The scratch-offs on the back revealed the date. We used VistaPrint (http://www.vistaprint.com/) to get the postcard and a family friend was able to give us circle scratch offs to place on the date.
I also created an electronic save the date for the website for those that we were
sending electronic invitations to. I used Adobe Flash and saved it as a movie to upload to the website.
I was not able to upload it for viewing.