DjZoNe

This plugins main goal was to provide the ability to any of your registered users, to invite more people to the community.
Please notice, that this plugin totaly ignores whether the registration is enabled or disabled to your blog.
<a href="https://downloads.wordpress.org/plugin/invite-friends.0.3.zip" rel="nofollow ugc">Download now!</a>
<a href="http://invite-friends.dev.rain.hu/" rel="nofollow ugc">Support</a> | 
<a href="http://invite-friends.dev.rain.hu/faq/" rel="nofollow ugc">FAQ</a> | 
<a href="http://djz.hu" rel="nofollow ugc">Author</a> 
<a href="https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=djzone@cracker.hu&item_name=Invite%20Friends%20for%20Wordpress" rel="nofollow ugc">Donate</a>
Some functions:
<ul>
<li>invitation sending</li>
<li>invitation cards limit per site</li>
<li>after activation, the user is logged in automatically</li>
<li>after activation, the user can be redirected to a custom URL</li>
<li>activation screen is using the same styles as the login screen (if you have customized login screen it will affect the activation screen as well)</li>
<li>Dashboard for custom settings Plugins > Invite friends settings</li>
<li>i18n support (localized messages)</li>
</ul>

Invite Friends

This plugin give the ability to anyone how registered to your blog, to invite more people, even if the registration is closed.

Aenon Dynamics

Andi Dittrich

NOTE: this plugin is targeted to advanced users and professionals – it requires some configuration tasks and won’t work out-of-the-box!
The plugin is used to display Email addresses as an image – automatically. 
This will stop harvesters and crawlers from gathering sensitive data from your website. 
It works with emails, telephone numbers, postal addresses or any other text-content. 
Just wrap your E-Mail-Address into a shortcode like <code>[email]youraddress@example.com[/email]</code> – that’s it. 
Or use the Autodetect filter to transform every E-Mail-Address on your page automatically into an image!
<h4>Plugin Features</h4>
<ul>
<li>Protects Email Adresses, Telephone Numbers or any other content</li>
<li>Fully customizable appearance: you can configure font-family, font-size and font-color – everything looks like your theme style</li>
<li>Retina/HD/High-Dpi Images – best appearance on all devices (2x, 3x or 4x resolution enhancement)</li>
<li>Shortcode and/or Autodetection usage!</li>
<li>Build-In E-Mail-Address-Autodetection – all addresses on your page are protected automatically (if you want it – you can also just use shortcodes!)</li>
<li>Autodetection filters configurable for the_content, the_excerpt, comments, comments_excerpt, text-widget</li>
<li>Reversible Address-Autodetection Process – your content is modified as long as the plugin is activated</li>
<li>Postal-addresses, telephone-numbers, names and other sensitive information`s can be protected too</li>
<li>Protects E-Mail hyperlinks (mailto) by using javascript based key-shifting encryption/decryption with dynamic keys – but you can use images only</li>
<li>Suitable for high traffic sites – automated caching of dynamic generated images and CSS</li>
<li>Automatic font-search (standard system font-paths)</li>
<li>Supports the new modern UI style of WordPress 3.8</li>
<li>Native support for <a href="https://wordpress.org/plugins/enlighter/" rel="ugc">Enlighter Syntax Highlighter</a> to display E-Mail Addresses within highlighted content (requires Enlighter v2.7)</li>
<li>Includes the <a href="https://fedorahosted.org/liberation-fonts/" rel="nofollow ugc">Liberation(tm) Fonts</a> package</li>
<li>TrueType as well as OpenType Fonts are supported</li>
</ul>
<h4>Text-Transformations</h4>
The @-sign as well as dot’s within the e-mail-addresses can be automatically replaced by different placeholders, e.g. <code>mail(at)example{dot}org</code>, to match your website’s corporate design.
<h4>Security Modes</h4>
Cryptex provides various obfuscation modes for E-Mail-Addresses:
<ul>
<li>Plain Text – only text-transformations are applied – no use of images</li>
<li>Single Image – the e-mail-address is expressed as a single image </li>
<li>Multipart Image – the e-mail-address is splitted into two images, seperated by the @-sign in plain text</li>
<li>Advanced Multipart Image – the craziest one: each part (divided by dot’s and @ sign) is displayed as a seperate image, the dividers as plain text</li>
</ul>

Cryptex | E-Mail Address Protection

Cryptex transforms plain-text E-Mail-Addresses into Images - automatically - No scrapers. No harvesters. No spambots. That's our goal!

Invite Friends vs Cryptex | E-Mail Address Protection