Now it is possible to install Google software like picasa directly from repositories.

This is really good specially to stay with the latest versions of software using your normal application management tool.

Debian and Ubuntu
If you are using Debian Etch or Ubuntu Feisty proceed as follows (as root)

Get the file https://dl-ssl.google.com/linux/linux_signing_key.pub and save it in your HOME directory, then import the key.

apt-key add $HOME$/linux_signing_key.pub

Edit your /etc/apt/sources.lst file and add.

# Google software repository
deb http://dl.google.com/linux/deb/ stable non-free

update your database.

apt-get update

and you are done.

Fedora

For your Fedora proceed as follows as root.

Add this file google.repo in /etc/yum.repos.d/ directory.

the file should have this lines.

[google]
name=Google - $basearch
baseurl=http://dl.google.com/linux/rpm/stable/$basearch
enabled=1
gpgcheck=1

And that is all.

Mandriva

Mandriva users have it really easy just one command as root:

urpmi.addmedia -v google http://dl.google.com/linux/rpm/stable/i386 with hdlist.cz

Now if you want to do it using the graphical environment rather than the command line go to this page