I know exactly what you mean. (I love Chrono Trigger

)
But, it's generally the whole idea of 'lost technology' in almost anything fantasy... The civilization was defined by it, but something went wrong (depletion/over-dependance) and you have a catastrophe.
Think 500 years from now?
No oil. No coal. No natural gas. No methane hydrates. Not even the tar sands or oil shale. Is there really going to be 20+ billion people on the planet? Even about 8 billion?
Are we going to be a nuclear + renewable + genetic engineering society?
Or are things so complicated and dependant on fossil fuels that we are going to crumble or collapse?
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Tales of Eternia
Another RPG that sorta goes along with Peak Oil in a tangential sort of way I thought is Tales of Eternia (I think that's what its called? It's for Gamecube... main character is named Lloyd.)
Anyways, so in the game there is these two worlds that depend on a power source and it is so that only one world can have it working at a time... So, one world is either small villages and failing tech (only very few devices work) and the other is this super-high tech civilization.
In a way, it paralled the whole U.S. Peak Oil talking point about how the United States is a huge consumer of energy (is it 25%) and produces only about 5% (not sure about the statistic, but it's low). If you put 'economics' aside and look purely at what's happening; it's like we are sucking fossil fuels that enable our 'world' to become what it has become from the 'other world' (the Middle East (some parts can be exceptions I think) and Africa).
Generally, every once in awhile, the energy-techonology switches to the other civilization. And there is a rebellion working to switch the power on to their side.
(There is also some more complicated stuff I can get into about how in the game the two worlds were one at a time, but they became separated by some plot point... and that has connections to our own Earth as we have these two different worlds. Seriously, you can parallel the majority of the plot of the game into a very 'liberal' 'anti-free trade' 'anti-corporate' world view thing... or it could be that the game was sorta based on colonialism stuff... This probably won't make sense to the majority of the people reading this anyways.)
Final Fantasy 7
Also, Final Fantasy 7 has some things that you could decide to read it as a world halfway through the depletion side of the curve... That FF7: Advent Children movie that came out in Japan (and has been subbed on the internet) has a character (Barret) exclaiming joy about how he found oil. What's interesting is that in FF7, I got the impression he and his group were originally eco/corporate-terrorists - but that's because of a different 'resource' which was being exploited by the 'evil corporation'.
(Also, early on in Final Fantasy 7, you fight suburban houses. YOU FIGHT HOUSES! Now, this I think I can read as 'suburbia'... You can draw whatever conclusion you want from that...)
That game was great when it came out. Now that I think about it... It had a great mix of personal confusion of the self mixed in with its super-green idealogy hidden inside a game with great graphics (at the time) and a cool new system of leveling. Huh... and I always thought that Cloud was just cool for swinging a sword bigger than him.