Guess what! The little tricks of skype does not have an end ... The Linux users of Skype recently discovered that it is reading the /etc/passwd and firefox profile files. COME ON? Do you continue using Skype?
The original post is here: http://forum.skype.com/index.php?showtopic=95261
And some explanations can be found here: http://www.oreillynet.com/sysadmin/blog/2007/08/a_close_look_at_questionable_a.html
But I seriously consider using Skype ...