UnixKit-tiny

UnixKit for Windows is a toolkit of Unixlike programs for Microsoft Windows. Unlike CygWin, it does not require installation. In fact, it leaves absolutely no traces on the host machine when you’re done using it.The -tiny branch presently includes:arc arj bash bunzip2 bzip2 bzip2recover cat chmod cksum cp csplit cut dd df diff du file find fmt fold funzip grep gunzip gzip head join less ln ls md5sum mkdir more mv nano nl paste patch pico pr rm rmdir sed sort split stat tac tail tar touch tr tsort uniq unrar unzip uudecode uuencode vi wc wget zip zsh

It looks like the original link to this site http://jlb.twu.net/code/unixkit.php is no longer working, however, thanks to the magic of the Wayback Machine you can click here to see the original page and visit Quad Lasers to download.

Update 02/09.2008:

Also check out GnuWin32 and UnxUtils.