Don't forget Rick Warren's version of "Purple Haze".
I wonder if you could take "Eye of the Tiger", change the lyrics to reflect "Heart of the Christian", and have a pretty snappy church-tune?
That'll be sure to bring 'em in!
Puff the Magic Dragon:
"Jesus the magic saviour lived by the sea
in a land called Galaleeeeeeeee"
Why do I have the feeling it's already been done!