Rob Flickenger authored the majority of hacks in this book.
Rob has worked with Linux since Slackware 3.5. He was previously the system administrator of the O'Reilly Network (an all-Linux shop, naturally) and is the author of Building Wireless Community Networks, also by O'Reilly.
Rael Dornfest ([Hack #87])
Rael is a Researcher at the O'Reilly & Associates focusing on technologies just beyond the pale. He assesses, experiments, programs, and writes for the O'Reilly network and O'Reilly publications.
Seann has been working with UNIX since 1987 and now architects high availability solutions as a senior systems engineer with D-Tech corporation in Dallas, Texas. He holds a Master's degree in Computer Science from Texas A&M University. He may be reached at: http://seann.herdejurgen.com/.
Dru Lavigne ([Hack #39])
Dru is an instructor at a private technical college in Kingston, ON where she teaches the fundamentals of TCP/IP networking, routing, and security. Her current hobbies include matching every TCP and UDP port number to its associated application(s) and reading her way through all of the RFCs.
Cricket Liu ([Hack #77])
Cricket matriculated at the University of California's Berkeley campus, that great bastion of free speech, unencumbered Unix, and cheap pizza. He worked for a year as Director of DNS Product Management for VeriSign Global Registry Services, and is a co-author of DNS and BIND, also published by O'Reilly & Associates.
Mike Rubel ([Hack #42])
Mike (http://www.mikerubel.org) studied Mechanical Engineering at Rutgers University (B.S. 1998) and Aeronautics at Caltech (M.S. 1999), where he is now a graduate student. He has enjoyed using Linux and GNU software for several years in the course of his numerical methods research.
Jennifer Vesperman (all of the CVS pieces except [Hack #36] were adapted from her online CVS pieces for O'ReillyNet)
Jenn contributes to open source, as a user, writer and occasional programmer. Her coding experience ranges from the hardware interface to an HDLC card to the human interface of Java GUIs. Jenn is the current coordinator and co-sysadmin for Linuxchix.org.
Schuyler Erle (contributed code for httptop, mysql-table-restore, balance-push, find-whois, and vtundgen)
By day, Schuyler is a mild-mannered Internet Systems Developer for O'Reilly & Associates. By night, he crusades for justice and freedom as a free software hacker and community networking activist.
Kevin Hemenway, better known as Morbus Iff, is the creator of disobey.com, which bills itself as "content for the discontented." Publisher and developer of more home cooking than you could ever imagine, he'd love to give you a Fry Pan of Intellect upside the head. Politely, of course. And with love.