I think a clever use of Open Source is reusing and adapting
code written by others.


20071101 -
phpexcel - excel reader.

20070127 -
php4 domxml to php5 dom code: 
Alexandre Alapetite, http://alexandre.alapetite.net/

I have taken code and ideas from the following projects:

Etomite    : the installer
Mantis     : custom fields, ldap authentication, lang_api, database class
Eventum    : some javascript
Dotproject : ideas for custom fields and database class


Icons/images
Some icons and images has been taken from: http://www.famfamfam.com/

franciscom
