MUST BE 21! The group's tag line is "Community Service with a Social Twist." If you are under 21, you can still search their upcoming events to see if you could contact the organization to help out and just not attend the festivities afterwards.
Mostly about events and things going on around Columbus. However, they often post about volunteer opportunities or needs.
Many organizations have Twitter feeds or Facebook pages to get the word out. Follow those you are passionate about. Additionally, blogs in the Columbus area post news about groups that need help.