The Banach integral is elegant in its definition, and I am intrigued as to why it is so rarely seen. Is it in practice difficult to calculate from the definition? And are there any other problems with it? I would also be interested to see examples of functions that are Banach-integrable, but not Lebesgue-integrable, and functions (if any) whose Banach and Lebesgue integrals over some interval are defined but different.
 **Added in response to comments:** The Banach integral is defined in [*The Encyclopaedic Dictionary of Mathematics*](http://books.google.co.uk/books?id=azS2ktxrz3EC&pg=PA1167&lpg=PA1167&dq=banach+integral&source=bl&ots=MZbE-yvuoN&sig=iZirxsujVkKuCkN0YlvpGqNRZkE&hl=en&sa=X&ei=GQO6T4-HJsWP8gOlqey0Cg&ved=0CNQDEOgBMAE#v=onepage&q=banach%20integral&f=false). Like the familiar Riemann integral, it's an integral for real functions over a real interval, and not applied to general Banach spaces (except perhaps in some generalization that I know nothing about). 



Is there a good comparative study of the Banach integral?
One can find some information in the German language book *Reelle Zahlen* by Oliver Deiser. Banach apparently introduced his integral in the paper [Sur le problème de la mesure](http://matwbn.icm.edu.pl/ksiazki/fm/fm4/fm412.pdf), Fund. Math. 4, 1923. It was apparently introduced to show that a translation invariant and finitely additive extension of Lebesgue measure on all sets of real numbers exist. 


The Banach integral of a Riemann-integrable function coincides with the Riemann integral. There is a function whose Banach integral is $0$ that is not Lebesgue integrable. Also there are Lebesgue integrable functions whose Banach integral differs from The Lebesgue integral. The Banach integral is linear, but not "countable additive". The last fact explains that one cannot do all the nice limiting arguments one is used to when working with the Lebesgue integral. 


