UPDATE: There seem to be some questions about the safety and reliability of this tool. When I have some free time I am going to conduct a behavioral analysis to vet the tool. Please refrain from using it until its been validated as safe.
I just discovered an interesting new site, reclaimprivacy.org, which according to the site admins is designed "to promote privacy awareness on Facebook and elsewhere."
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The site works by "scanning your Facebook privacy settings" and warning you "about settings that might be unexpectedly public."
hat tip to Drew Conway (@drewconway)