The Peer-to-Peer Trusted Library (PtPTL) is a software security toolkit tailored for the creation of peer-to-peer applications. It allows for the establishment of trust between individual peer-to-peer clients and the organization of secure groups of trusted peers. Ultimately, the PtPTL allows users to share information and collaborate securely across the Internet.
The ax25-apps package contains programs for the hamradio protocol AX.25 that would be used by normal users (as opposed to network daemons). While not essential, these programs are usually installed if you want to connect to amatuer packet radio networks. Generally it is a good idea to also get the ax25-tools package so you can configure the hamradio ports. This package includes call, listen, ax25ipd and ax25rtd.
LSM (Loadable Security Module) is a very simple but effective intrusion prevention loadable kernel module. Current functionality involves protecting extended file attributes on ext2 from being modified by the super user and the module from being removed and other modules from being loaded. The basic protection also prevents access to raw devices, so debugfs can not be used on a disk partition nor can a change to the boot process occur. You will not be able to reconfigure lilo, if the module gets activated.
Cdred is a Linux driver and two programs that enables *any* CD player software (xfreecd, gtcd, etc) to use audio cdroms inserted in another computer. In other words: you can listen an audio cd in a Linux box that doesn't have that cd inserted. Cdred works on all 2.2.x kernels, support for 2.4 will be implemented soon.