At a former workplace the theme was sci-fi authors. At one point I noticed that all the Windows and Linux boxen were named after men and the Macs after women, which seemed vaguely appropriate, so that became a further informal convention. Mostly the names were chosen arbitrarily, but we had a G4 iMac which was called 'shelley' for presumably non-arbitrary reasons.<p>For my personal machines I decided to implement the same male/female scheme but for a theme I am using 'people somehow associated with Pink Floyd' e.g. vera, torry, storm, mallet, emily. I used to joke that if Apple ever came out with an x86 Mac I would have to call it 'layne', but they did, and I realized that PF (to my knowledge) only ever did one song about a transvestite, so that would not be a sustainable convention. :)