It requires MS powerpoint to open ,, for poor MAC s like me pps is not worth the hassle of installing a viewer.
for you MS folks due a google search on BBQinvatation.pps and you will find a few links to it.
the html (Without picture) did sound like it might be funny
PS have your virus checkers up to date http://www.joe-ks.com/MultiMedia/BBQInvitation.htm
i don't know the site