Some members of the still-young CUNY Academic Commons, eager to start groups in support of various projects, have been getting hung up on the process of putting a group together: first, each person has to sign up for the Commons; second, each person has to become friends with the group admin; third, each person has to request membership or wait to be invited (in the case of private groups). I just released a plugin called Invite Anyone that cuts out the second step: with the plugin activated, group admins can invite anyone from the installation, not just friends.
Read more about it, and download the plugin, at the CUNY Academic Commons Dev blog.
EDIT: Please leave further comments or questions regarding this plugin at its permanent home: Invite Anyone
The New BuddyPress plugin: Invite Anyone by Boone Gorges, unless otherwise expressly stated, is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.