Science, Skepticism, and Flat Earth

The amount of scientific investigation had lead to a situation where far more information about the universe is known than any one person could ever learn. Therefore, even though science is all about openness and reproducibility, everyone can't check everything. Therefore, even though some people know that quantum theory works or know how an engine works, most other people only believe quantum theory is what physics professors say, or believe that engines work the way engineers say they do. For a few aspects of science, some random group of people for whatever reason decides not to believe blindly. Since science is open and reproducible, these people could learn and know that whatever they doubted is true, but scientists are usually not the best at making such information easily available and comprehensible.
When people are skeptical of a claim, there are a few methods of dealing with it. As discussed here, one can investigate scientifically, i.e. proposing hypotheses and then developing experiments to test them. A scientist will then admit when an hypothesis is falsified by those experiments, and work on a new one. A "kook" will generally not do experiments, but instead insist that others do them to prove things. Kooks will then reject as biased or inaccurate any experiment that does not produce the results they wanted. An interesting case study of this phenomenon is the Flat Earth Society, who have decided that the Earth is actually flat, and that the US, Russian and Chinese governments and space agencies are conspiring to hide that information. Given the case they present, most people probably believe the Earth is round, but do not know it. Here I will demonstrate how a scientist would investigate this question.

The conventional model:

The earth is an oblate spheroid with a polar radius or 6356.8 km and an equatorial radius of 6378km. Due to gravitational interaction, it orbits the sun, which has a radius of 6.96E8m, with a semi-major axis of 149597887.5km once every 365.256 days (the .256 creates the need for leap days).
For more information, see The Sun and The Earth Wikipedia pages.

The flat earth model:

Information from The Flat Earth Society Homepage.
The earth is a 24900 mile disk, with the North pole at its center. The sun and moon are 32mile diameter spotlights at a height of 3000miles that circle the north pole over the equator. Since they are spotlights, only part of the earth is illuminated at any given time. Gravity is not real, things fall because the earth, moon, and sun are accelerating upward at 9.8m/s.

The evidence:

geometry and astronomy:

Sunrise and sunset and time zones are superficially addressed by the flat earth model, but in a very hand wavy way. The sun appears to rise in the east and set in the west. North of the Tropic of Cancer, the sun is always to the south of vertical, and south of the Tropic of Capricorn, it is always to the north. The flat earth model described would predict that the sun would not move more than a few degrees from vertical, and rather than setting, would just appear to fade out.
The ancient Greek, Eratosthenes calculated the radius of the Earth in 240 BCE. His method begins with the knowledge that the sun is far enough away to be treated as a parallel ray source, which can easily be demonstrated. Then the difference in angle between the sun and the ground in two different locations is used to determine the difference in ground orientation between the two locations.
travel time between cities-> distance between cities
One can see satellites, and the international space station, for more information, see heavens-above.com.
More evidence the ancient Greeks noticed: when a ship was approaching shore, the masts and sails became visible first, then the rest of the ship, while on a flat earth, one would expect to see the entire ship at all times until it became a featureless dot. At the flat earth forum here people seemed unable to comprehend that point.

inertia:

 Coriolis effect & hurricanes
The following devices demonstrate the difference between an inertial frame and the rotating earth:
Foucault's Pendulum
gyroscope
or with modifications a gyrocompass

gravity:

Gravity has been observed to vary from the poles to the equator and with altitude.
The Cavendish experiment which is used to determine the gravitational constant. It involves a torsional pendulum (a bar with two lead balls on the ends supported by a wire), which twists according to the force applied. Placing more lead spheres near the ones suspended on the wire causes a measurable deflection, which allows the gravitational attraction between the spheres in the horizontal plane to be measured. Pasco sells one for physics lab classes. This effect was mentioned in a flat earth forum and its scientific merit was completely ignored.

Conclusion

I am posting the following message on a flat earth society forum:
There are many observations one can make that fit a round earth model but not a flat earth one. Many of them have already been brought up in these forums, and never satisfactorily answered. To save space and repetition here, I will simply provide a link ([url]http://qbsmd.spaces.live.com/blog/cns!5BA0601679A003C2!111.entry[/url]) containing all of those observations. The purpose of this post is to ask what, if any observations do you claim support a flat earth model, that do not support a round earth model?