First Better GMail, now Better GReader:

http://lifehacker.com/software/exclusive-lifehacker-download/trick-out-google-reader-with-better-greader-262020.php

[via digg]

Not forgetting Better Gcal (released last week by same site)
I'm loving all 3, but would like more options for GReader

Wow all of those are great. The Gmail one is the best in my opinion.

yes. and its the only one i am using. :)

I like not the Better GReader

Better MySpace would be a great extension.

Maybe I'm old fashioned but I like to install the Greasemonkey scripts. It's easier to enable / disable them, to edit the code and I only need one extension, not 100: Better Gmail, Better Calendar, Better Yahoo Autos, Better Google Sets etc.