Ubuntu Privacy
Remove zeitgeist and all of the components
# sudo apt-get purge zeitgeist-core zeitgeist-datahub python-zeitgeist rhythmbox-plugin-zeitgeist zeitgeist geoclue geoclue-ubuntu-geoip
# rm -rf ~/.local/share/zeitgeist/
clear cache
# cat /dev/null > ~/.bash_history && history -c && exit
For a more heavy duty cleaning use
# bleachbit