Two-way isn't just for playing cards, apparently

[drboone]

I recently stumbled upon the Brazilian banknote series of 1978-80, where both sides are more or less two-way. (The backs actually aren't quite; see if you can find it in the attached image.) Maybe KWP Legal Tender...?

[Honeybee]

It is a subtle miss on the backs while the 2 way heads look bloody awful

[drboone]

The design choices are very odd. Having the right side up portion of the front be the right side, the duality of the central vignettes mirroring sideways but the edges mirroring clear across, etc. Can't say as I care for the effect overall, but it is an interesting and as far as I know relatively unique choice on currency.

[GandalfPC]

Both artistic choice and practical one - making handling of the bills easier by man and machine - not used anymore though, as at least one of those has advanced, and the other proven fickle