As of version 0.7.4, it includes:
Kernel 2.4.27, Abiword, siag, Dillo, Firefox, Captive-NTFS, gaim, ethereal, vim, Sylpheed, XMMS and plugins, Imposter, IceWM, wavplay, mpg321, FreeNX, John the Ripper, Tcl, qemu, kismet, abcde, macchanger, screen, paketto, ogg123 and other Ogg Vorbis tools, axyFTP, fireftp, rox-filer, cdrecord, mkisofs, rdesktop, tcpdump, parted, partimage, xfsprogs, Rhapsody, didiwiki, torsmo, GNUpod, GRUB, dsniff, aircrack, madwifi, dnsmasq, foremost, antiword, e2undel, iftop, bbpager, utelnetd, minicom, index, gpart, socat, traceroute, SciTE, prozilla, Midnight Commander, Samba, elmo, tmsnc, apsfilter, gmplayer, mount.app, chntpw, tinycc, nano, Xzgv, Xpdf, naim, hdparm, usbview, index, recoverdm, mtr, cdparanoia, betaftpd, Chipmunk Basic, gqcam, e3, lua, cdparanoia, giFTcurs, mtools, emelfm2, vncdec, elhttp, quagga, ettercap, wavemon, iptables, recover, amap, hping2, cabextract, splitvt, pciutils, LinNeighborhood, nmap and nmapfe, portmap and nfs-common, aumix, CTorrent, VNCviewer, sqlite, SSH and SCP, DHCP client, xtdesktop, PPP and PPPoE support, NTFS resize support, an RSS reader, stress, cpuburn, the Monkey webserver, Xcalc, Fluxbox, evilwm, the XBase apps, and the various standard console and system tools.
First, I stripped all the packages from Knoppix 3.4 that I didn't need - after all, who needs both KOffice and Openoffice.org, and about five window managers? That left me with a 70Mb image, and then I removed all the locale files and documentation I could find. I also changed the standard XFree86 server to the XVesa and XFbdev servers, which are quicker and much smaller. Then I removed /var/lib/dpkg and placed it in a separate .tar.bz2 archive (which can be downloaded for remasters or hard drive installs), and I did the same for /usr/src/linux as well.
Next, I started adding some more applications which were both Debian and non-Debian, such as Abiword and Xzgv respectively. I also removed some files which were identical to others, and replaced them with either symlinks or shell scripts (i.e. in the case of grep, egrep and fgrep). After that, it was just a case of cleaning up some remnants of the original Knoppix - I changed the boot image to show the Feather Linux bootup screen, and I also prevented /home/knoppix from being overwritten on boot.