wp_title Help. Simple, I think?

Hello,

I have been playing around with my blog titles and notice a small, mainly irritating bug that happens when a post does not have a headline.

Right now, my blog displays the title as: My Name / Title.
When I view a post that does not have a title, it displays as: My Name /

Is there a way I can default the title to something I choose?

Thanks a million,
Ian.