*nod*, the AI still doesn't go exponential enough in the modern era. I find that I tend to have a handful of specialized high-production cities (that use mines and the like), which then build wonders that leverage that high production to make it ridiculous production (national epic for a unit factory, ironworks for a wonder factory, etc). The AI is horrid at city specialization. Part of this is that the 5th AI shouldn't value the tech that highly any more. The value of trading away a tech to an infinite number of clients should be roughly the value of researching the tech. But that isn't how the AI values technology. Suppose we revalued technology to be worth (1/2^n) times it's lightbulb value, where n is the number of empires that have the technology. So if you research a technology worth 1000, you can trade it away for 500 gold to the first person, 250 to the 2nd person, 125 to the 3rd person, etc. With a large number of other players "on side", you could tech up using only their gold paying for it -- they would also get the technology, however. In the case that two civilizations know different sets, we could use the average of what each civilization thinks it is worth. Dunno. Yes -- I think the AI's resource value code is still stuck in the pre-corporation model, where a 2nd resource isn't worth as much as the 1st by orders of magnitude.