I'll spare you the details, but my client just passed away and I would like to place an announcement on their website. I'd like it to load in an area (250px height by 400px width) over the splash page (index.html) with the site dimmed behind it. I'd also like it to be a one-time load so it doesn't re-open after the initial page visit.

Is there an ingenious way to handle this without a lot of page renaming/hand-coding?