Fisher Space Pen, from me...(I personally have a silver Bullet pen). Cool specifications: 1. Can write at any angle without running out of ink due to pressurized ink cartridge. 2. Can write in extreme temperatures, from -30 to 250 degrees F. More (from Wikipedia...)
The ballpoint is made from tungsten carbide and is precisely fitted in order to avoid leaks. A sliding float separates the ink from the pressurized gas. The thixotropic ink in the hermetically sealed and pressurized reservoir is claimed to write for three times longer than a standard ballpoint pen. The pen can write at altitudes up to 12,500 feet (3810 m). The ink is forced out by compressed air at a pressure of nearly 35 pounds per square inch (240 kPa). Operating temperatures range from -30 to 250 degrees Fahrenheit (-35 to 120 degrees Celsius). The pen has an estimated shelf life of 100 years.