The historically libc5 based <b>Slackware Linux</b> has been upgraded to use the newer, and much more popular glibc based libaries upon which
RedHat Linux, Debian, etc are based. If you're interested, check out 
<a href="ftp://sunsite.doc.ic.ac.uk/Mirrors/ftp.cdrom.com/pub/linux/slackware-current">ftp.cdrom.com</a>.