Fletcher T. Penney
fletcherpenney@sourceforge.net
Fletcher is the author of the original perl script. This was originally a command line perl tool that used shadow files and disk images to create a whole new means of performing backups on OS X machines. xrBackup is a descendant of the originall project.
You can learn more about Fletcher, and see his other Mac/*nix projects at his website.
Moritz Borgmann
Moritz created the first native Cocoa GUI for the rbackup.pl script, which was the inspiration for the xrBackup project.