The Utah Teapot was made by Martin Newell. Actually, one of it's nicknames is the Newell Teapot. It's more well known as the Utah Teapot, though.
The real teapot's actually 33% taller than the computer model. Jim Blinn, who was a computer graphics expert at NASA's Jet Propulsion Laboratory, scaled down the model slightly during a demo in the lab to demonstrate that they could manipulate it. He and Mr. Newell preferred this edited version and saved the file that way.
It's an in-joke inside people who work on computer graphics. My favorite appearance is the Windows Pipes screensaver, where instead of a ball joint, a 'teapot joint' would appear.