Digital Wikipedia is not epic anymore.
Printed books is where it's at.
Abbreviated version: one-volume feature articles.
Regarding an offline digital version: I think it would be useless. Wikipedia links to other websites. If you would want to have complete references, you would need to include those websites as well.... and the websites they refer to. In the end, you would end up with an offline version of the internet, and I don't think that's the point of the internet