To make a note of: a categorized collection of over 300 freeware utilities: http://www.econsultant.com/i-want-freeware-utilities/index.html
I found some to be quite good:
- chat with the jabber network : Pandion // compatible with Google Talk
- backup mozilla (firefox/thunderbird) browser profile : MozBackup
- burn/create CD/DVD iso image files : ISO Recorder