What is this addon?

[solshine2510]

Hello, I have been browsing through Post your UI thread to hopefully find some inspirations for tweaking my own UI and found a screen with addon that is totally obscure to me.
Since I cant post any links untill I post a few more times, I'll have to describe it: the user that posted the screenshot had a row of capital letters under his action bars, they were:

C P N L Y O J H ?.

Any idea what that might be?
If anyone would like to bother to check original post - it was submitted in "Post Your UI" thread, on 2011-01-19, page 109 (first post on that page), poster Buutch.

[Deleted]

http://www.wowinterface.com/download...MicroMenu.html