I found this through This French Life:
Do you have an ancestor who was decapitated during the Revolution? You can find out by checking out Les Guillontines, a website that listed all those that were condemned to die, deported or imprisoned during the French Revolution.
I don't have any French heritage on my side of the family, but I couldn't resist looking for my married name. And yes, there are three guys listed, but our family name is not especially unusual in France - it's not a "Smith" but I still see it from time to time - so there's no telling if they're really related. I couldn't help looking for my friends' names, too. I've found more than a couple. Is your family name listed?