gdivelog is a SCUBA dive logging application for GNOME. It has been developed for linux, but should build on most flavours of *nix

gdivelog has all the features a SCUBA diver expects of dive logging software and a few additional features not found in other dive logging software currently known to the author, for instance the ability to split and merge dives and a tree hierachy for dive sites. In addition to this gdivelog has a plugin based architecture allowing anyone to write a plugin to download/manipulate a dive computer, import and export data to and from other dive logs, create reports or essentially anything you want.