Mark (podz)

Make your website go viral by allowing users to spread the word!
This plugin gives your readers the ability to spread the word about your website simply by entering the e-mail addresses of their friends. The system will then send e-mails to these people to allow the word to be spread. You’ll soon be getting more visitors than ever before!

The Viral Widget

Make your website go viral by allowing users to spread the word!

Boone Gorges

CUNY Academic Commons

Invite Anyone has two components:
1) The ability to invite members to the site by email. The plugin creates a tab on each member’s Profile page called “Send Invites”, which contains a form where users can invite outsiders to join the site. There is a field for a custom message. Also, inviters can optionally select any number of their groups, and when the invitee accepts the invitation he or she automatically receive invitations to join those groups.
The email invitation part of the plugin is customizable by the BP administrator, via Dashboard > BuddyPress > Invite Anyone.
2) By default, BuddyPress only allows group admins to invite their friends to groups. In some communities, you might want members to be able to invite non-friends to groups as well. This plugin allows you to do so, by populating the invitation checklist with the entire membership of the site, rather than just a friend list.
Because member lists can get very long and hard to navigate, this plugin adds a autosuggest search box to the Send Invites screen – the same one that appears on the Compose Message screen – which allows inviters to navigate directly to the members they want to invite.
Invite Anyone features optional integration with CloudSponge http://cloudsponge.com, a premium address book service, that allows your users to invite their friends to the site in a way that’s easy and fun. Enable it at Dashboard > BuddyPress > Invite Anyone.
<h3>Translation credits</h3>
<ul>
<li>Belarussian: Alexander Ovsov (<a href="http://webhostinggeeks.com/science" rel="nofollow ugc">Web Geek Science</a>)</li>
<li>Brazilian Portuguese: Celso Bessa</li>
<li>Catalan: Mònica Grau and Toni Ginard</li>
<li>Danish: Mort3n</li>
<li>Dutch: Jesper Popma, Tim de Hoog</li>
<li>French: Guillaume Coulon, Nicolas Mollet</li>
<li>German: Lars Berning, Thorsten Wollenhöfer, Matthias Lunz</li>
<li>Greek: Lena Stergatou</li>
<li>Italian: Luca Camellini</li>
<li>Norwegian: Stig Ulfsby</li>
<li>Russian: Jettochkin, Roman Leonov</li>
<li>Serbo-Croatian: Anja Skrba</li>
<li>Spanish: Mauricio Camayo, Gregor Gimmy</li>
<li>Swedish: Alexander Berthelsen, Jan Anderson</li>
<li>Ukrainian: <a href="http://www.coupofy.com/" rel="nofollow ugc">Ivanka</a></li>
</ul>
Additional details about the plugin can be found in the following languages: 
* Serbo-Croatian: <a href="http://science.webhostinggeeks.com/teleogistic" rel="nofollow ugc">http://science.webhostinggeeks.com/teleogistic</a>

Invite Anyone

Makes BuddyPress's invitation features more powerful.

The Viral Widget vs Invite Anyone