The Fisher Space Pen is a revolutionary ballpoint pen which works with thixotropic ink and a pressurized ink cartridge. It can write on almost any substance ranging from butter to steel. It also can survive a wide array of temperatures, ranging from -50 to 160 degrees Fahrenheit.
Fisher submitted his invention to NASA. After vigorous testing, NASA approved Fisher's Space Pen. They purchased four hundred units at a reported price of $6.00. NASA purchased three different models: the 204, 207 and 208. The 204 had blue ink and a retraction button on the end. It was used on Skylab and the Apollo missions. It was later replaced by the 207. The 207 model was similar to the 204, except the retraction button had been moved to the side. The 208 model was the same as the 207, except it wrote in black ink. NASA modified these pens for use in the space program. Velcro patches were added along with a standard metal clip to facilitate the storage and attachment of the pen.
Fisher proposed the replacement of all existing sales and income taxes with a single graduated asset tax on those with assets of at least $100,000. He wrote a book published in 1988, The Plan: To Restore the Constitution and Help Us All Get Out Of Debt (ISBN 0961984309), to promote this idea.