Web-based software

CMS

Geeklog

Maybe not the best name, but solid, secure and easily extended.

Webmail

Squirrelmail

Good. Usually already installed everywhere.

Roundcube

The new kid on the block.

Project management

WebCollab

Works.

Photo album

Gallery

Does everything.

Zenphoto

The new kid on the block.

Web FTP

WebFTP

Not sure this is a great idea. Be safe.

Calendars

vcardphp

Parses vcards.

phpicalendar

Online calendars.

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