Too many ideas, not enough time

I might have mentioned in previous blog posts that I keep a notebook of story ideas. Whenever I come up with an idea that I think would make a great story, I jot it down in the notebook. It's usually just a couple of sentences to a paragraph. I have so many ideas now that I could easily spend the next decade writing them! Yet new ideas come up every week.

What's a writer to do when there are so many shiny, new ideas beckoning? Especially when motivation for the current project that I'm working...