Getting CiviCRM resources to load on the Joomla frontend
I found that on Joomla the default value for CiviCRM Resource URL (on Administer > System Settings > Resource URLs), which is [civicrm.root], doesn't work. For me, using a relative path for CiviCRM Resource URL does work:

administrator/components/com_civicrm/civicrm/


See also the answers to this question and the work being done by Coleman, but that patch didn't work on Joomla when I tried it.

EDIT: As of 4.7.17, the default setting of [civicrm.root] appears to work properly now.