Check to see if your desired username or vanity url is still available at dozens of popular Social Networking and Social Bookmarking websites.
Soziale Beziehungen in Geek-Sprache beschrieben ;)
Diese zeigt einem an, bei welchen Social Network man gerade eingeloggt ist
App Advisor helps safe-guard your personal data by telling you exactly which apps you should be cautious of, before they become a threat to your privacy.
It is an open-source Python-driven tool aimed at penetration testing around Social-Engineering.