A CG Auxillary buddy of mine alerted me to a $20 shareware program called NavRules which seems to be pretty good for learning dayshapes, sounds, and lights, both inland and international. It's only for windoze and not iFruits or Linux OS's. It has a pretty good update and bug update history since 1994. Apparently it has only recently been available for download from the web at http://www.navrules.com/download.html . About 872Kb in a self installing file. I think it'll replace the flash cards I currently use to keep up with COLREGS. 30 day trial period before you have to fork over the ducats. The author is a CG reservist and software programmer.