After finally getting themes support about 2 weeks ago, another Kupfer version (v206) was released today bringing a huge list of bug fixes and more importantly, reduced memory usage. The changelog says the Kupfer runtime memory should be reduced by 10-30% thanks to the reimplementation of icon cache.
You can check out all the bugs fixed in the latest Kupfer v206 here.
With this release, there's also good news for Ubuntu 10.04 users: the latest Kupfer has finally been packaged for Ubuntu Lucid Lynx too so you can finally install it from the PPA (until today the PPA provided a very old Kupfer version for Lucid).
Add the Kupfer PPA and install the latest v206 in Ubuntu 10.04, 10.10 and 11.04 using the commands below:
sudo add-apt-repository ppa:kupfer-team/ppa
sudo apt-get update
sudo apt-get install kupfer
Tip: Kupfer comes with 2 extra themes - to change the theme, go to the Kupfer Preferences and on the Plugins tab enable the "Custom Theme" plugin, then select among the other 2 themes: dark or square. If you want to create your own theme, see HERE.