I was having a lot of trouble getting rid of whitespace at the top of one of my applications. I did some investigating using comments to suss out the source of it, and realized that it was coming from cfc invocation using <cfobject>. I was thinking about caching them to the application scope anyway, as they are basically just big function libraries. And that got rid of it.

Had I been a little more dilligent in my investigation, I would have figured out that <cfcomponent> takes output="false" as attribute.

So it might be a lazy way of doing so, but caching cfc's can also have the side benefit of getting rid of whitespace.