The Official SBS Blog : Reclaiming Disk Space Lost to IIS Logs on SBS 2003: http://blogs.technet.com/sbs/archive/2008/02/28/reclaiming-disk-space-lost-to-iis-logs-on-sbs-2003.aspx
Read the complete post at http://msmvps.com/blogs/bradley/archive/2008/02/29/the-official-sbs-blog-reclaiming-disk-space-lost-to-iis-logs-on-sbs-2003.aspx