Opensource Webmaster Tools..

[Positive]

Opensource license :
For editing php and html scripts
Code:

http://notepad-plus.sourceforge.net/uk/site.htm

Archiving
Code:

http://www.7-zip.org/

3D design
Code:

http://www.blender3d.com/

Antivirus
Code:

http://www.clamwin.com/

FTP Manager and ftp server
Code:

http://filezilla.sourceforge.net/

Something like photoshop
Code:

http://gimp-win.sourceforge.net/

SOmething like all in one messenger
Code:

http://www.miranda-im.org/
http://gaim.sourceforge.net/screenshots.php

Somthing like dreamweaver
Code:

http://www.nvu.com/

ANd also some servers
Code:

mysql apache php

Office suite
Code:

www.openoffice.org

Also a freeware one :
WEllGET identicaly to flashget
Code:

http://www.wellget.com/

P.s. : Thanks to dongan for these links