There was a program on one of the cable channels that followed a coffee buyer to countries where that trip could end up as the last one, ever for the fellow.
Sadly I cannot find it now but it was very interesting.
He would buy and roast the green beans of non-standard species of coffee trees; some of the local band or tribes men knew the value of their beans being bought in bulk but still did not get even close to giving away the few beans he bought to roast.
In his tasting of one type, most of the show was about trying to get where he was going alive, anyway he said it was good coffee but Americans would never accept it as not what they expect, much less will accept coffee to taste like.
During the past ten years, I have spent more hours trying to find rare coffees pre-roasted but while there is a lot of talk of rare types, especially in Africa, getting some is a rare as hens-teeth.
I did get some excellent Philippine coffee but when I tried to re-order they were out of business due to import problems.
If you truly like coffee and want to get some that is different and extremely hard to find try Trung Nyugen coffee shop, they have the civet coffee, which I will never ever buy, but more importantly others you can get no where else.