How do you repair a lost filling until you can get to a dentist?

I had a porcelain filling in between my two front teeth, and It fell out yesterday. Now I have a gap there that feels like the grand canyon to me. Others say they can hardly notice it, but it is really bugging me. I am avoiding saying words with f’s and s, because I think I sound like Cindy Brady. Friends said I now have something in common with Madonna, but I think it;s more of a Lauren Bacall look. Any ideas how I can put it back temporarily? Not super glue. That’s too permanent. What can I do?