I have known of eix for a while, assuming it was just another emerge tool suite as app-portage/portage-utils or app-portage/gentoolkit. It turned out, it only specializes in searching ebuilds and does a great job on that.

Before I installed it, I rarely used emerge -s|-S to do package search, I used Google. Usually, gentoo packages [keywords] or more precise search inurl:packages.gentoo.org [keywords]. Why didnt I use emerge to search? Because its slow. After you use eix, you would say its damn slow.

eix supports boolean operator and it only takes a second or a few more to get the results. For example, you want to play a RPG game but you dont want a MMORPG type, you can

$ eix -S RPG --and --not -S MMORPG

Quick and simple. There are more than juse -S, read the man page for more.

Here is an example output of eix package:

http://farm5.static.flickr.com/4079/4899678062_c57e13e8dd_b.jpg

The output is fancier than emerges, I am still trying to get used of it.

The process of updating your system would be slightly changed, you have to update (eix-update) eixs cache after you sync Portage tree. But you can run eix-sync to do both task for you. The output is very useful:

http://farm5.static.flickr.com/4073/4899678182_21501ec196_b.jpg

It will compare the changes from last cache update, then you can decide whether if you want to continue to update your system. Also provide the time consumption of each tasks, you can see it took 128 seconds to do cache update. It seems to take too much time, but a few emerge search would take much more than that.

I think eix is a must-have program for your Gentoo.