I'm very interested in your code - the bar graph doesn't look too useful to me, as I'm pretty much always watching the screen anyway, so I at least have a general idea of how I've been doing. But, the storing of tank data, fuel cut indication, and DTE look very useful.
I think putting the code up on the wiki would be great, with some sort of disclaimer that adding all the extra code will take up more space, and may not fit on different Atmega chips.
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