The answer is here: http://en.wikipedia.org/wiki/Kopi_Luwak
Where coffee plants have been introduced into their habitat, civets only forage on the most ripe berries, digest the fleshy outer layer, and later excrete the seeds eventually used for human consumption. Thus, when the fruit is at its peak, the seeds (or beans) within are equally so, with the expectation that this will come through in the taste of the brewed coffee. The civet, by selecting the most flavorful beans, creates problems for the typical farmer, who often finds a significant portion of his best cherries missing in the morning after civets have been feeding. This led to a persecution of the civets, who in many regions became in danger of extinction. It is also possible that the quality of the civet coffee is somewhat reflective of the civet's natural ability to patiently select the best of the crop for consumption. Attempting to recover the lost crop led farmers to gather the civet droppings and try to reclaim them, resulting in the discovery that the droppings produced an exception coffee with unusual taste and lack of bitterness.
has anyone tried acid washing the beans to simulate this process?
oh wait.. maybe that is a million-dollar idea - forget I mentioned it
I'll bet it has an unusual taste.