BackTrack is the result of the merging of two Innovative Penetration Testing live Linux distributions - Whax and Auditor. BackTrack has been dubbed as the best Security Live CD today, and has been rated 1st in its category, and 32nd overall in Insecure.org. Based on SLAX (Slackware), BackTrack provides user modularity. This means the distribution can be easily customised by the user to include personal scripts, additional tools, customised kernels, etc

The image will be 850+ MB, so get them DVD's, or even better, USB keys ready. We will also have a VMWare image handy.
Now based on Debian core packages and utilizing the Ubuntu software repositories, BackTrack 4 can be used both as a Live CD, or installed on hard disk as a full distribution. By syncing with our BackTrack repositories, you will regularly get security tool updates soon after they are released.

Native support for Pico e12 and e16 cards is now fully functional, making BackTrack the first pentesting distro to fully utilize these awesome tiny machines.
Support for PXE Boot - Boot BackTrack over the network with PXE supported cards!
SAINT EXPLOIT - kindly provided by SAINT corporation for our users with a limited number of free IPs.
MALTEGO - The guys over at Paterva did outstanding work with Maltego 2.0.2 - which is featured in BackTrack as a community edition.
The latest mac80211 wireless injection pacthes are applied, with several custom patches for rtl8187 injection speed enhancements. Wireless injection support has never been so broad and functional.
Unicornscan - Fully functional with postgress logging support and a web front end.
RFID support (thanks to Adam Laurie)
Possibly CUDA support...
New and updated tools - the list is endless!