FYI, I just saw a special on NOVA tonight about the man (I can't quite remember his name) who solved the "longitude" problem with sea navigation. I believe it was titled "Lost at Sea", or something of the sort, most likely it's been aired before and been mentioned on this list.
Very interesting how he realized that, in the case of accuracy onboard a ship, smaller was actually better. I had read about him in a Smithsonian article (mentioned before on this list), and it was neat to see the clocks he made worked. Also intriguing how he came up with a system of keeping a pendulum at the correct length no matter the temperature, by using lengths of different metals.
