The IQ League maintain a "60 Second IQ Test" online. Interestingly, they correlate the results of this test with a number of statistics available from their server logs. Along with the geographical distinctions like city and country, the referrer and OS/Browser user-agent strings are also mined, to determine the Smartest Browser and OS. Cutting to the chase, the very smartest is Firefox on Unknown (which internal evidence suggests is MacOS-Intel), and the dumbest, as of this writing, is IE on WinNT.
(Hat tip: Slashdot)
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