I just realized that a lot of you out there probably don't know about this. We've all heard about the planned visual refresh for Intrepid. Well, if you want to try out some of the themes that have been created, you can install them in Hardy and stay up to date with their improvements using kwwii's PPA. Just add these lines to your /etc/apt/sources.list:
deb http://ppa.launchpad.net/kwwii/ubuntu hardy main deb-src http://ppa.launchpad.net/kwwii/ubuntu hardy main
sudo aptitude update && sudo aptitude install community-themes, and you're good. Intrepid's sound theme is also in that PPA, so if you don't want the login sounds to change, disable the PPA again after you get the themes installed.
I really like the Kin theme.