If you like me who likes Opera browser, you may want to add this into your sources.list file:
## Opera
# wget -O - http://deb.opera.com/archive.key | sudo apt-key add -
# deb http://deb.opera.com/opera/ sid non-free
# deb http://deb.opera.com/opera-beta/ sid non-free
deb http://deb.opera.com/opera/ stable non-free
deb http://deb.opera.com/opera/ testing non-free
deb http://deb.opera.com/opera/ unstable non-free
Update: You may want to use the official Howto at
https://help.ubuntu.com/community/OperaBrowser instead.
This would allows you to get the program and its updates through aptitude
