How to search super-quickly in all the remote Gentoo overlays with eix-remote

You probably know eix the portage indexer. If not, you should use it.
I just discovered that and it is awesome, too bad the documentation doesn't explain/sell it well enough.
First add a remote index, gpo is building a cache for you :
eix-remote fetch "http://gpo.zugaina.org/eix_cache/eix-cache.tbz2"
Then, tell eix to not drop this remote index after eix-update by setting KEEP_VIRTUALS=true in your /etc/eixrc:
# cat /etc/eixrc 
Update your remote index !
eix-remote update
Now if you want to search in the remote indexes, just add -R (for remote) in your search
eix -R scratch
Eix will differentiate clearly the remote indexed ones from the local / portage ones

Enjoy !