Blancpain's Bathyscaphe is the greatest dive watch of all time. This particular example, which  features an impeccable gloss dial and a hefty steel case, is both desirable and unbelievably rare (by any standards). With beautifully-patina'd hour markers and hands that have taken on a cream hue, you can't get more of a vintage aesthetic than this. Will I ever find another Technisub again? Probably not. Will I regret selling it? Probably yes. But at least I can say that I owned one...for a few days :-)