Inserting on a view listing

I have a view that calls up a list of posts (For a typical column view of Title, Thumbnail, Excerpt) — Maybe it's 30 posts per page. How would I be able to INSERT something else every 5 posts down? For example, call up advertising?

I know I could make multiple views. One calling a view with the 1st 1-5, then 5-10, etc – but that's a painful answer. Is there another method?

THANKS!