Mileage minimizer!
 

A while ago I was shown online a page where you could input something like the following:
2 passengers ex LHR
3 passengers ex JFK
4 passengers ex SIN
5 passengers ex HKG

The tool would then calculate where you should all meet to minimize the CO2 emissions - based purely on distance flown (so, please, no replies telling me how futile it is as different aircraft and different engines have different emissions and so on :) )

Does anyone out there know the webpage for this? I've searched here back to 2005, and googled this, but without success so far. Anyone knows about this planning tool?

I know TripIt can do something similar with adding an emissions summary to trip plans.

http://www.carbonneutralcalculator.c...alculator.aspx
http://www.travelnav.com/flight-emissions/
https://carbonfleet.net/shop/offsets?offset_type=Flight

Those were just the first three I found searching for flight emissions calculator. Hopefully sufficiently generic for your needs.

Not quite what I was after
 

Thanks to SBM12, but those are not what I am after. The site I saw did not primarily focus on the CO2-emissions from any given leg. Instead, given a number of people from different locations, it would calculate where they should all meet to minimize emissions.

The tool was mentioned on the Economist's site some years ago. Anyone else remembers this and can point me to it?

Why would you want to minimize your miles?

Got it on my first try! :)

http://lmgtfy.com/?q=find+place+to+m...inimize+travel

The first search result seems to work.