If Fuelly were to add a view of cars by average mileage and filter based on different parameters I think it would be an awesome feature.
I honestly did tons of random clicking and read so many different articles which used EPA ratings while those are okay they are nothing like seeing real world reports from users like me. And then I always came back to Fuelly to make sure there were people in the real world getting these numbers or exceeding them. This would be something very helpful to many people making considerations on buying a new vehicle. Just a suggestion.
I think that's a good way to do it. You can use Fuelly as a check against manufacturer or EPA estimates you already know.
We don't want to sort cars by mileage because that would encourage gaming the system. Once there's a leaderboard there will be people who want their car (or their favorite model) to be at the top of that leaderboard. We have some info about this here: Why don't you list everything in order of best fuel economy?
That makes sense, it's a shame that one could expect such behavior, because it would be really nice to have an option to sort vehicles by fuel economy. It's useful to me to see the hypermiled ones if you want to compare potential fuel economy. It's way easier to differentiate plausible, thorough logs and useless data (fueled up twice then left, keep very erratic logs) when you don't have to browse through the whole flock for the 'gems'.
Even it if was sorted by car model, that would be useless data in any case, because different engines/fuels etc are all together. i.e., 'VW Passat 2013' could include anything from a 4 litre performance car with an W-8 cylinder engine and 4-wheel drive to a bluemotion eco-car using a diesel engine.
Hence a leaderboard based on the fuelly model would not be useful for finding the top eco-cars.