Easiest CMS system to use?

[DXL]

I have a client that would like to make frequent updates to a particular page on his site. Is there a free CMS program out there that I can install on the server so that he can log in somewhere and then make a simple update to that one page? It has to be something relatively easy to learn, and extremely easy to use.

[Mr Bo Jangles]

Google for these two:
flyspeck asbru

both would seem to do the job pretty well

[DXL]

Flyspeck looked pretty cool, thanks. I wish I could download a demo before buying it, though.