The crew of a Caribou passing through Bali quite a few years back needed to "motivate" the local refueller in the usual way. Lacking any rupiah, they used the ES4 form (the government miscellaneous requistion form that they carry).
One can only surmise the look of the bean counters when the copy of the form arrived back in OZ appended, "Bribe for refueller".
I believe they paid up anyway.