BackTrack is probably the single best security distribution of Linux. The Remote-Exploit team has been around for a few years now and is really coming into maturity with their announcement today of the release of BackTrack 4 Beta. BackTrack 3.0 was a huge success for them with it having been downloaded more than 3 million times.
BackTrack is a Live CD (version 4 is installable) that is focused on security and exploitation of security vulnerabilities. There are always items in the news about how easy it is to hack into someones wireless network or computer. BackTrack contains the multitude of those tools that make this possible.
The toolset is very well designed and can help both beginners and advanced users to test their security. You can download the beta which is considered stable enough for usage however there have been some tools excluded from the beta until other issues are resolved.
Check It Out> Remote-Exploit, Download BackTrack Beta, via Hack a Day
UPDATE:: The distribution is password protected. To logon use the following:
Username: root
Password: toor
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