Template:Clear

Assuming you've got images floating on one side of the page, this template separates them from all the content below. Good for gallery headers that get orphaned from a gallery. Oh, and chicks dig it.

This header is not after {{Clear}}.

If you've got a gallery (or similarly wide content) right below a header, you'll end up with a shitload of whitespace between the header and the crap you meant to show. (For the vast majority of users and resolutions.)

This header is after {{Clear}}.

Need another example? Pull up an old version of Bitches don't know and look at the whitespace between the "Gallery" header and the gallery itself. Ugly, huh? Kids would add an arbitrary number of line breaks manually to get around it, but it's not even remotely precise. Sure, there may be more white space than you like, but that's because Headers and images come with a ton of padding.