Loving RoundCube
What's better than a Cube? A rounded cube!
After my I-hate-all-webmails post (sorry, in Spanish), I must recognize I have found one which is pretty decent (also very mac-ish): Round Cube.
It's still in alpha but works greatly and nicely, super ajax powered... and it's so clean...!
If you want to try it, use these installation instructions. Pretty straightforward.
A MUST have - I think it'll become the web2.0 webmail program ;-)