Over at alistapart, there is an article on embedding or inserting flash files into websites. The article covers the current situation of flash embeds and the techniques that can be used to insert files into pages. In covers the issues of cross-browser compatibility of flash insertion techniques and what the future might hold for flash on the web.
Although I am not a big fan of swf or Adobe Flash files embedded in websites because of the current accessibility issues (although this may be changing), flash elements in church webpages can have a powerful visual impact. Much more than a static picture. But with any of these things, too much flash can have users switching off.