What the hell did I install ?!

So I got a new laptop from my work. I have already my IBM x60s running Gentoo. I want to install my new Lenovo x200 with about the same configuration.
So what did I installed on my IBM x60s?

cat /var/lib/portage/world

shows you all the packages you have ran 'emerge package'. It will not show you all the dependencies that portage have added, so its a clean list of packages you installed.

I copy the world file to my fresh install and edit it deleting packages I don't need.
But wait! Don't install this packages yet. You will download lot of blobs that you have already.
In my x60s all the packages are stored in /usr/portage/distfiles/.
So I just copy all the files from the old computer to the new computer. I do it with rsync, but you can do it with scp, cp+sshfs etc.

rsync -avPn --exclude=svn-src /usr/portage/distfiles/* x200/usr/portage/distfiles/

Lets make sure we have all the blobs:

emerge --fetchonly $(cat copied.world.file)

Now we can install everything ;-)

emerge $(cat copied.world.file)

Simple!

Regards,
Kfir