Copied from DistroWatch http://distrowatch.com/?newsid=02962#0
The developers of the PHLAK project are working on a new USB pen drive edition of their Linux distribution. The first beta of PHLAK "LittleBoy" was released for testing today: "I developed this version with USB pen drives in mind. You can boot 'LittleBoy' completely from USB pen drives, as long as the computer supports USB booting. It is small (currently 195MB), lightweight (Fluxbox GUI only), fast (thanks to USB 2.0), but still packs a punch (almost all security tools still included)! The goal here is to refine our tool collection and other package selections to make LittleBoy the perfect size for a 256MB USB pen drive. Later on maybe we can refine it even further for a tiny security distro, ~50MB." Find more information and changelog in the release announcement. Download from here: phlak-littleboy-beta1.iso (195MB, MD5).
Mirror site for the download. http://ftp.osuosl.org/pub/phlak/phlak-littleboy-beta1.iso
I haven't tried it yet. Downloading right now.