Is there a program to remove libraries which were pulled in by apt-get as prerequisites, but are no longer needed by anything? For example, my system has libgtkhtml17, 18, 19, and 20. The three former versions are not required by any installed package -- they just consume disk space. It would be neat if apt-get remembered what packages were pulled in as dependencies, and offered to remove them when they fall out of the dependency tree. -jwb