Joomla Most Popular Extensions that are not Joomla 1.5 Native

The Community Builder suite extends the Joomla! and Mambo website user management systems and allows to manage those users. Current version is 1.1 compatible with all Joomla! 1.0.x (including 1.0.15) and Mambo 4.5.2-4.6.4.
Although New CB version 1.2 RC brings Joomla 1.5 native compatibility (and keeping Joomla 1.0.x and Mambo 4.5.2-4.6.4 native compatibility)

Alternatives - Joomunity - builds dynamic and vibrant community sites on the worlds most successful CMS – Joomla. With lots of inspiration from popular networks like Facebook, MySpace, Netlog and Beboo, joomunity compiles a set of USEFUL and EASY to build applications to enable effective collaboration amongst Joomla Site users. (Please note it is still in beta stage, latest release is 1.1.0.b2)

SOBI 2 - Sigsiu Online Business Index 2 is a directory component for the WCMS Mambo and Joomla! to show entries of companies, clubs, persons, shops, products.
It does work with Joomla 1.5 though, but in lagacy mode.

Alternative - AlphaContent 4.0.7 - AlphaContent is a component that allows the creation of directories such as Yahoo from sections and categories on your site Joomla!.
Another Alternative is JoomSuite Resources (Commercial) - This component allows create unlimited numbers of directories(sections) with unlimited and multi leveled categories.
But SOBI 2 is still the best directory component, AlphaContent just turns your content into Yahoo style, But lacks the custom fields, custom template, 3rd party plugins, and directory submission features of SOBI 2. MosetTree does have some of those features unfortunately it's not free and it's not joomla 1.5 native either.

joomlaXplorer is a File- and FTP - Manager. It allows you to edit files, delete, copy, rename, archive and unpack files/directories directly on your server.
Alternatives - NinjaXplorer - is a Joomla 1.5 Native fork of JoomlaXplorer., eXtplorer - is a web-based File Management Component for all your needs.

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