Cleaning up Ubuntu

I've been going through my ubuntu install and trying to free up some diskspace. Came across quite a few neat tools to clean up the Ubuntu install, especially unused packages installed using aptitude.

The following have easy to follow instructions:
http://ubuntuforums.org/showthread.php?t=140920

http://benhodge.wordpress.com/2008/02/17/cleaning-up-a-ubuntu-gnulinux-system/

I haven't tried to remove orphaned packages because I read that this could mess up your system, so use at your own risk.

Also try xdiskusage, its available through aptitude and gives you a good overview over what folders take up the most space.