A very cool visualization of the imigration / emigration data:
To remember: the relative sizes of countries / continents on most maps is not representative of the true ratios, because most map projections were not meant for that. If you want to play around with different projections, here is a nice page from Wolfram (unfortunately you have to install a ~100MB plugin to get it to work). If you need the raw data, just go to Wikipedia.
Finally, here is a good essay from Asimov (from 1989) about the scientific process: The Relativity of Wrong – small nitpick: it would have been even better if it had used the metric system or at least it didn’t switch from miles to inches in he middle of the essay.